criyle/codenet-compile-errors huggingface dataset:
Language: C++

#define _USE_MATH_DEFINES

#include <iostream>

using namespace std;

int main()
{
	int n;
	cin >> n;
	printf("%.10f\n", 2 * n * M_PI);

	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:11:35: error: 'M_PI' was not declared in this scope
   11 |         printf("%.10f\n", 2 * n * M_PI);
      |                                   ^~~~
Language: C

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, n) for(int i = 0; i < (n); i++)
#define pb push_back
const int maxn = 10000;
const int INF32 = 1'050'000'000;
const long long INF64 = 4'000'000'000'000'000'000;
const int MOD7 = 1'000'000'007;
const int MOD9 = 1'000'000'009;

void ERROR(int num) { printf("ERROR%d!\n",num); }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
int dx[8]={-1,0,1,0,1,1,-1,-1};
int dy[8]={0,-1,0,1,1,-1,1,-1};
const double PI = acos(-1);

int main(){
	double R;
	cin >> R;
	double ans = 2 * PI * R;
	//cout << ans << endl;
	printf("%.20lf",ans);
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
main(){
long long i,j,k,l,m,n,o,p;
while(cin>>n){
cout<<n*2*3.14159<<endl;
}
return 0;
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
#define ll long long
int main()
{
  ll n;
  cin>>n;
  n=2*n;
  double p=3.1415926536;
  p=(double)p*n;
  printf("%.5lf\n",p);
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
# define M_PI           3.14159265358979323846  /* pi */
int main()
{
    int r;
    std::cin>>r;
    std::cout<<2*(M_PI)*r<<endl;
    return 0;
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: Java

import java.util.*;
class circlepond{
  public static void main(String args[]){
    Scanner in = new Scanner(System.in);
	int r = in.nextInt();
    System.out.println(2*3.14.r);
 }
}

Compiler output:
Main.java:6: error: double cannot be dereferenced
    System.out.println(2*3.14.r);
                             ^
1 error
Language: C

#include <bits/stdc++.h>
#define PI 3.14159265359
using namespace std;

int main() {
  float r;
  cin>>r;
  float C;
  C=2*r*PI;
  cout<<C;

}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <iomanip>
#include <algorithm>
#include <cstdio>
#include <cstring>
#define For(i,a,b) for(i=(a); i<(b); i++)
using namespace std;

const double pi=3.1415926;

int main(){
	double r;
	cin>>r;
	cout<<2*pi*r;
	return 0;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define rep(x,to) for(int (x)=0;(x)<(to);(x)++)
#define rep2(x,fr,to) for(int (x)=(fr);(x)<(to);(x)++)
#define sz(v) (int)(v).size()
using namespace std;
typedef long long ll;
int main()
{
	cin.tie(0);
	ios_base::sync_with_stdio(false);

	double PI=3.14159265358979323846;
	double R;
	cin >> R;

	cout << R * 2 * PI << '\n';
	return 0;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C++

#include<iostream>
using namespace std;
int main(){
  int a;
  cin>>a;
  int ans=a*6.28318530717958623200;
  cout<<and<<endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:7:12: error: expected identifier before '<<' token
    7 |   cout<<and<<endl;
      |            ^~
Language: C++

#define ll long long
using namespace std;
const int maxn = 2e5+5;
//inline void fastio() {ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);}
 
int _;
 
int main()
{
    //fastio();
    double r;
    scanf("%lf",&r);
    printf("%.8f\n",r*2*acos(-1));
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:12:5: error: 'scanf' was not declared in this scope
   12 |     scanf("%lf",&r);
      |     ^~~~~
a.cc:13:25: error: 'acos' was not declared in this scope
   13 |     printf("%.8f\n",r*2*acos(-1));
      |                         ^~~~
a.cc:13:5: error: 'printf' was not declared in this scope
   13 |     printf("%.8f\n",r*2*acos(-1));
      |     ^~~~~~
a.cc:1:1: note: 'printf' is defined in header '<cstdio>'; this is probably fixable by adding '#include <cstdio>'
  +++ |+#include <cstdio>
    1 | #define ll long long
Language: C

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main(){
	int R;
	cin >> R;
	cout << (double)2*R*M_PI;

	return 0;	
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
 
int main() {
  double r;
  cin >> r;
  cout << r * 3.14159;
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

import math
import queue

def readInt():
	return int(input())

def readInts():
	return list(map(int, input().split()))

def readChars():
	return input().split()


r = readInt()

print(r*2*3.14159265)

Compiler output:
main.c:1:1: error: unknown type name 'import'
    1 | import math
      | ^~~~~~
main.c:2:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'import'
    2 | import queue
      | ^~~~~~
main.c:2:1: error: unknown type name 'import'
Language: C

#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)


int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int R;
    cin >> R;
    cout << fixed << setprecision(10);

    cout << 2*R*3.1415926535<<endl;


}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rrep(i, n) for (int i = 1; i < (int)(n); i++) 
#define dunk(n) cout << n << endl
#define all(a) (a).begin(),(a).end()
typedef pair<int,int> P;
typedef long long ll;

int main() {
    double r;
    cin >> r;
    r = 2*r*3.1415926535;
    cout << fixed << setprecision(20) << r << endl;
    return 0;
}

Compiler output:
main.c:2:10: fatal error: bits/stdc++.h: No such file or directory
    2 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define fi first
#define se second
ll sieve[1000001]={0},i,j;
ll m=1e9+7;
ll lev=0;
ll n,k;
ll power(ll p, ll k)
{
ll a=1;
while(k)
{
if(k&1)
a=(a*p)%m;
p=(p*p)%m;
k>>=1;
}
return a;
}
using namespace std;
vector<ll> v[1000000+1];
ll vis[1000000+1]={0};
void dfs(ll u,ll p,ll lev)
{
    vis[u]=lev;
for(auto x: v[u])
{
if(x!=p)
{
dfs(x,u,lev+1);
}
}
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
 int tc=1;
//cin>>tc;
ll cas=1;
 while(tc--)
 {
  
  ll r;
  cin>>r;
  cout<<3.14*r; 
     cout<<"\n"; 
 } 
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define f first
#define s second
using namespace std;
typedef long long ll;
const int INF = 1e9;
const ll INFl = 1e18;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef set<int> si;
typedef map<int,int> mii;
typedef unordered_map<int,int> umii;
typedef queue<int> qi;

int main() {
	ios::sync_with_stdio(false); cin.tie(0);
	long double x;
	cin >> x;
	long double y = 2.00000 *  3.14159265359 * x;
	cout << fixed << setprecision(6) << y << '\n';
	
	return 0;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;
#define rep(i,ini,n) for(int i=ini;i<n;i++)
const double PI=3.14159265358979323846;

int main(){
    int r;
    cin>>r;
    cout<<PI*r*2<<endl;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> ii;
typedef tuple<ll, ll, ll> iii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
#define REP(i,n) for (ll i = 0; i < n; ++i)
#define REPR(i,n) for (ll i = n-1; i >= 0; --i)
#define FOR(i,m,n) for (ll i = m; i < n; ++i)
#define FORR(i,m,n) for (ll i = n-1; i >= m; --i)
#define FORE(x,xs) for (const auto& x : xs)
#define FORI(i,v) for (auto i = v.begin(); i != v.end(); i++)
#define ALL(v) v.begin(), v.end()
#define CHMIN(x,y) x = min(x, y)
#define CHMAX(x,y) x = max(x, y)
#define YES(b) cout << ((b) ? "YES" : "NO") << endl
#define Yes(b) cout << ((b) ? "Yes" : "No") << endl
#define DOUBLE(d) cout << fixed << setprecision(15) << (d) << endl

ld R;

int main() {
    cin >> R;
    DOUBLE(6.28318530717958623200 * R);
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using Graph = vector<vector<int>>;

const ll LINF = 1e18;
const int INF = 1e9;
const ll MOD = 1000000007;

template<class T> inline bool chmin(T& a, T b){
    if(a > b){
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b){
    if(a < b){
        a = b;
        return true;
    }
    return false;
}
vector<bool> seen;
void dfs(const Graph &G, int v){
    seen[v] = true; // vを訪問済みにする
    
    for(auto next_v: G[v]){
        if(seen[next_v]) continue; // next_vが探索済みならスルー
        dfs(G, next_v); // 再帰的に探索
    }
}

int main(){

    double r;
    cin >> r;
    double pi= 3.1415926535;
    cout << 2 * r * pi << endl;
    return 0;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
#define rep(i,n) for(int i=0;i<(n);++i)
#define dunk(a) cout << (a) << endl
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).rbegin(),(a).rend()
using namespace std;
typedef long long ll;

int main() {
	int r; cin >> r;
	double ans = 2 * r * 3.141592653589793;
	cout << ans << fixed << setprecision(10);
	return 0;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
long long int R;
int main()
{
	cin>>R;
	cout<<6.28*R<<endl;
	return 0;
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

r=int(input())
print(r*2*3.1415926535)

Compiler output:
main.c:1:1: warning: data definition has no type or storage class
    1 | r=int(input())
      | ^
main.c:1:1: error: type defaults to 'int' in declaration of 'r' [-Wimplicit-int]
main.c:1:3: error: expected expression before 'int'
    1 | r=int(input())
      |   ^~~
Language: C++

#include<bits/stdc++.h>

#define pb push_back
using namespace std;
 
int main()
{
 
 	#ifndef ONLINE_JUDGE
  

    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);

 	int r;
 	cin>>r;
 	cout<<(float)2*M_PI*r;
 	


	return 0;
}

Compiler output:
a.cc:9: error: unterminated #ifndef
    9 |         #ifndef ONLINE_JUDGE
Language: C

#include <bits/stdc++.h>
using namespace std;

int main() {
  double r;
  cin >> r;
  cout << 2.0*r*3.1415926535 << endl;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int N = 1e5 + 5, mod = 1e9 + 7;


int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    long double r;
    cin >> r;
    cout << fixed << setprecision(10) << 2.00 * r * 3.14159265359;

    return 0;

}




Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

r=int(input()
print(2*r*3.141592)

Compiler output:
main.c:1:1: warning: data definition has no type or storage class
    1 | r=int(input()
      | ^
main.c:1:1: error: type defaults to 'int' in declaration of 'r' [-Wimplicit-int]
main.c:1:3: error: expected expression before 'int'
    1 | r=int(input()
      |   ^~~
Language: C

/*---------------------------------------------------------------------*/
/*                   -------------------------------------             */
/*                   -----------MEHEDI HASAN--------------             */
/*                   -----CSE,JAHANGIRNAGAR UNIVERSITY----             */
/*                   -------------------------------------             */
/*---------------------------------------------------------------------*/
#include<bits/stdc++.h>
//#include <cassert>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//using namespace __gnu_pbds;
using namespace std;
/*---------------------------------------------------------------------*/
#define FAST        ios_base::sync_with_stdio(NULL);cin.tie(NULL);cout.tie(NULL);
#define cc(x)       cout<<#x<<"="<<x<<" ";
#define ccc(x)      cout<<#x<<"="<<"("<<x.ff<<" "<<x.ss<<") ";
#define CC(x)       cout<<"["<<#x<<"] = ";for(auto xx: x) cout<<xx<<" ";
#define CCC(x)      cout<<"["<<#x<<"] = ";for(auto xx: x) cout<<"("<<xx.ff<<" "<<xx.ss<<") ";
#define MARK(x)     cout<<x<<" ";
#define ee          cout<<"\n";
#define OK          cout<<"Ok till line "<<__LINE__<<"\n";
/*---------------------------------------------------------------------*/
#define ff          first
#define ss          second
#define ll          long long
#define ull         unsigned long long
#define pii         pair<int,int>
#define mp          make_pair
#define ps          push
#define psb         push_back
#define psf         push_front
#define pp          pop
#define ppb         pop_back
#define ppf         pop_front
#define all(x)      x.begin(),x.end()
#define TESTS       int t;cin>>t;for(int tcase=1;tcase<=t;tcase++)
#define ordered_set tree< int, null_type, less_equal< int >, rb_tree_tag, tree_order_statistics_node_update>
/*---------------------------------------------------------------------*/
#define MAX (int) (5e5+88)

int main()
{
    FAST
    int r;cin>>r;
    cout<<2*3.1416*r<<endl;
    return 0;
}
/*--------------------------------------------------------------------*/
/*
>Check Corner Cases (n==1 or T==1)
>Overflow issues?
>LB / UB !!not found!! check?
*/
/*--------------------------------------------------------------------*/
/* ---INPUT---
--------(1)------
4
3
AAB
5
AABAA
1
B
4
BABA
-------(2)-------
5
5
AAAAA
6
BBAAAA
1
A
2
BA
10
AAAAAAAAAB


-------(3)-------


-------(4)-------



--------------
*/
/*--------------------------------------------------------------------*/


//https://codeforces.com/contest/466/problem/C try again


Compiler output:
main.c:7:9: fatal error: bits/stdc++.h: No such file or directory
    7 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C++

#include"bits/stdc++.h"
#include<boost/multi_array.hpp>
#include<boost/optional.hpp>
#include<boost/range/irange.hpp>
#include<boost/range/algorithm.hpp>
#include<boost/range/adaptors.hpp>
using namespace std;
namespace adaptor = boost::adaptors;

void Main()
{
	int R;
  
  	cin >> R;
    
    printf("%lf", 2 * R * 3.1415)
	
	
}

int main()
{
	std::cin.tie(nullptr);
	std::ios_base::sync_with_stdio(false);
	std::cout << std::fixed << std::setprecision(15);
	Main();
}

Compiler output:
a.cc:2:9: fatal error: boost/multi_array.hpp: No such file or directory
    2 | #include<boost/multi_array.hpp>
      |         ^~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
Language: C

def resolve():
	n, m = map(int, input().split())
	a = list(map(int, input().split()))
	print(n-sum(a) if n-sum(a) > -1 else -1)


Compiler output:
main.c:1:1: error: unknown type name 'def'
    1 | def resolve():
      | ^~~
main.c: In function 'resolve':
main.c:1:14: error: expected declaration specifiers before ':' token
    1 | def resolve():
      |              ^
Language: Java

import java.util.*;
public class segment_tree {
    public static void main(String[] args) {
        Scanner rv=new Scanner(System.in);
        int r;
        r=rv.nextInt();
        System.out.println(2*3.14*r);
    }
}


Compiler output:
Main.java:2: error: class segment_tree is public, should be declared in a file named segment_tree.java
public class segment_tree {
       ^
1 error
Language: C

#include<iostream>
#include<cstdlib>
#include<cstdio>
#include<string>
#include<iomanip>
#include<algorithm>
#include<vector>
using namespace std;

int N, M;
string S;
long double R;

int main(){

    cin >> R;

    cout << 2.0*acos(-1)*R;


}


Compiler output:
main.c:1:9: fatal error: iostream: No such file or directory
    1 | #include<iostream>
      |         ^~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;

int main() {
  double x;
  cin >> x;
  cout << fixed <<setprecision(10);
  cout << x*2*3.14 <<endl;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int (i)=0; (i)<(n); (i)++)

int main(){
	int R;
	cin >> R;
	cout << 2*R*3.141592653589 << endl;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include  <iostream>

using namespace std;

int main(){

	double n;

	cin >> n;

	cout.precision(10);
	cout.setf(ios::fixed);

	cout << 2*3.14159265359*n << endl;

	return 0;
}


Compiler output:
main.c:1:11: fatal error: iostream: No such file or directory
    1 | #include  <iostream>
      |           ^~~~~~~~~~
compilation terminated.
Language: C++

#include<iostream>
using namespace std;
int main()
{
  int R;
  cin >> R;
  cout<< 2*pi*R<<endl;
  
 return 0; 
}

Compiler output:
a.cc: In function 'int main()':
a.cc:7:12: error: 'pi' was not declared in this scope
    7 |   cout<< 2*pi*R<<endl;
      |            ^~
Language: C++

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double db;
int main(){
    int n;
    cin>>n;
    printf("%.10f",2*n*3.141592535)
}   

Compiler output:
a.cc: In function 'int main()':
a.cc:8:36: error: expected ';' before '}' token
    8 |     printf("%.10f",2*n*3.141592535)
      |                                    ^
      |                                    ;
    9 | }
      | ~
Language: C++

#include <stdio>

const double PI=3.14159265358979323846;

int main() {
  double r;
  std::cin >> r;
  std::cout << r * PI *2.0 << std::endl;
}

Compiler output:
a.cc:1:10: fatal error: stdio: No such file or directory
    1 | #include <stdio>
      |          ^~~~~~~
compilation terminated.
Language: C

#include <vector>
#include <iostream>
#include <string>
#include <math.h>
#include <algorithm>
#include <bits/stdc++.h>


using namespace std;


int main(void){
  
  int R;
  double ans=0;
  
  
  cin >> R;

  ans = 2 * M_PI*R;

  cout << ans << endl;
  

  return 0;
}




Compiler output:
main.c:1:10: fatal error: vector: No such file or directory
    1 | #include <vector>
      |          ^~~~~~~~
compilation terminated.
Language: C++

#inlcude <iostream>
using namespace std;
int main(void){
 int R;cin >> R;
 cout << (double)2*R*3.141592653 << endl;
return 0;
}

Compiler output:
a.cc:1:2: error: invalid preprocessing directive #inlcude; did you mean #include?
    1 | #inlcude <iostream>
      |  ^~~~~~~
      |  include
a.cc: In function 'int main()':
a.cc:4:8: error: 'cin' was not declared in this scope
    4 |  int R;cin >> R;
      |        ^~~
a.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | #inlcude <iostream>
a.cc:5:2: error: 'cout' was not declared in this scope
    5 |  cout << (double)2*R*3.141592653 << endl;
      |  ^~~~
a.cc:5:2: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:5:37: error: 'endl' was not declared in this scope
    5 |  cout << (double)2*R*3.141592653 << endl;
      |                                     ^~~~
a.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
  +++ |+#include <ostream>
    1 | #inlcude <iostream>
Language: C

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int r;
	cin>>r;
	float ans;
	ans=2*(float)r*3.14159;
	cout<<ans<<endl;
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
#define rep(i,n)for(int i=0;i<n;++i)
#include<string>
#include<vector>
using namespace std;
typedef long long ll;
typedef pair<int, int>P;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
//max=({});
//条件式が真ならwhileの中身を回し続ける
//printf("%d\n", ans);

//pairの入力
//vector<pair<ll, ll>>work(n);
//rep(i, n) {
//	ll a, b;
//	cin >> a >> b;
//	work[i] = make_pair(a, b);
//for(auto p:mp)(mapの探索)
//printf("%.10f\n",なんちゃら)

int g[15][15];
const int INF = 1001001001;
const int dx[4] = { -1,0,1,0 };
const int dy[4] = { 0,-1,0,1 };

//最大公約数
ll gcd(ll x, ll y) {
	return y ? gcd(y, x % y) : x;
}

ll lcm(ll x, ll y) {
	if (x == 0 || y == 0)return 0;
	return (x / gcd(x, y) * y);
}

//素因数分解
vector<pair<ll, int>>factorize(ll n) {
	vector<pair<ll, int>>res;
	for (ll i = 2;i * i <= n;++i) {
		if (n % i)continue;
		res.emplace_back(i, 0);
		while (n % i == 0) {
			n /= i;
			res.back().second++;
		}
	}
	if (n != 1)res.emplace_back(n, 1);
	return res;
}

vector<ll>relation[20], money(20, 1);

int main() {
	double n;
	cin >> n;
	double ans = 2 * n * M_PI;
	printf("%f\n", ans);
	return 0;
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <math.h>
#include <functional>
#include <iomanip>
#include <bitset>
#include <numeric>
#include <queue>
#include <map>
#include <cstdint>
using namespace std;
#define rep(i, n) for (int i = 0; i < n; i++)
const long long mod = 1000000007;
typedef long long int ll;
typedef pair<ll, ll> P;
const vector<int> di = { -1, 0, 1, 0 };
const vector<int> dj = { 0, 1, 0, -1 };
const long double PI = acos(-1);

int main() {

	long double r;
	cin >> r;

	cout << long double(2 * r * PI) << endl;
	
	return 0;
}



Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C


// Problem : A - Circle Pond
// Contest : AtCoder - AtCoder Beginner Contest 163
// URL : https://atcoder.jp/contests/abc163/tasks/abc163_a
// Memory Limit : 1024 MB
// Time Limit : 2000 ms
// Powered by CP Editor (https://github.com/cpeditor/cpeditor)


/**         srijan_de
 _____      _ _              ______     
/  ___|    (_|_)             |  _  \    
\ `--. _ __ _ _  __ _ _ __   | | | |___ 
 `--. \ '__| | |/ _` | '_ \  | | | / _ \
/\__/ / |  | | | (_| | | | | | |/ /  __/
\____/|_|  |_| |\__,_|_| |_| |___/ \___|
            _/ |                         
           |__/           23.02.2001     **/
///.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.
#include    <bits/stdc++.h>  
using       namespace       std;
using       lli=            long long  int;
using       ulli=           unsigned long long int;
using       ld=             long double;
#define     mem(a,val)      memset( a,  val,  sizeof(a) )
#define     b_s             binary_search
#define     u_b             upper_bound
#define     l_b             lower_bound
#define     nl              cout<<endl
#define     pb              push_back
#define     pf              push_front
#define     ppb             pop_back
#define     ppf             pop_front
#define     in              insert
#define     fi              first
#define     se              second
#define 	pqueue			priority_queue
const lli   MOD=            (int)1e9 + 7;
const lli   MOD1=           (int)1e9 + 9;
const lli   MOD2=           998244353;
const ld    pi=             atan2(0, -1);
const ld    eps=            1e-9;
lli         tests=          1;
template<class x,class y>x max(x a,y b){return (a>b)?a:b;}
template<class x,class y>x min(x a,y b){return (a<b)?a:b;}
template<class x,class y>x log(x n,y r){return (n>r-1)?1+log(n/r,r):0;}

///.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.
int32_t main() 
{
	auto start = clock();
ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);	

//	cout<<fixed;
//	cout<<scientific;
	cout<<fixed<<setprecision(20);
	// cin>>tests;
	for(lli test=1;test<=tests;test++) 
	{
//		cout<<"Case #"<<test<<": ";
///.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.
		
		
		
		lli n;
		cin>>n;
		cout<<double(2*n*pi);
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
		
///.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.
	}
	cerr<<endl<<endl<<endl<< "Time : " << double(clock() - start) / CLOCKS_PER_SEC <<endl;
	return 0;
}
///.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.


Compiler output:
main.c:20:13: fatal error: bits/stdc++.h: No such file or directory
   20 | #include    <bits/stdc++.h>
      |             ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;

int main() {
	int r;
	double c;
	cin>>r;
	c=(44.0*r)/7;
	cout<<c;
	return 0;
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>
#include <cmath>
using namespace std;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
using Graph = vector<vector<int> >;
// MOD
const int MOD = 1000000007;

long long GCD(long long a, long long b) {
    if (b == 0) return a;
    else return GCD(b, a % b);
}

int H, W;
int field[100][100];

const int dx[2] = {1, 0};
const int dy[2] = {0, 1};
const double PI=3.14159265358979323846;
bool seen[100][100];

int main() {
    double r; cin >> r;

    cout << 2.0*PI*r << endl;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>

using namespace std;



int main()
{
    long long int n;
    cin>>n;
    cout<<2*M_PI*n;
    return 0; 
}



Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define INF 1e9
using namespace std;

#define REPR(i,n) for(int i=(n); i >= 0; --i)
#define FOR(i, m, n) for(int i = (m); i < (n); ++i)
#define REP(i, n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define ALL(a)  (a).begin(),(a).end()
#define endl "\n"

template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return true; } return false; }
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return true; } return false; }
typedef long long ll;

const double PI=3.14159265358979323846;
void solve() {
    double d;
    cin >> d;
    cout <<fixed << setprecision(10)  <<  d*2*PI << endl;
}

int main() {
    solve();
    return 0;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;

int main(){
  int a;
  cin >> a;
  cout << 2*a*3.1415;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <string>
#include <map>
#include <vector>
#include <algorithm>
#include <iostream>
#include <string>
#include <map>
#include <vector>
#include <algorithm>
#include <cmath>
using namespace std;
#define ll long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define Graph vector<vector<int>>;
#define iterG(next_v, G, v) for(auto next_v : G[v]
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int r;
    cin >> r;
    cout << 2 * r * M_PI << endl;
    return 0;
}



Compiler output:
main.c:1:10: fatal error: string: No such file or directory
    1 | #include <string>
      |          ^~~~~~~~
compilation terminated.
Language: C++

#include<iostream>
#include <string> // string, to_string, stoi
#include <vector> // vector
#include <algorithm> // min, max, swap, sort, reverse, lower_bound, upper_bound
#include <utility> // pair, make_pair
#include <tuple> // tuple, make_tuple
#include <cstdint> // int64_t, int*_t
#include <cstdio> // printf
#include <map> // map
#include <queue> // queue, priority_queue
#include <set> // set
#include <stack> // stack
#include <deque> // deque
#include <unordered_map> // unordered_map
#include <unordered_set> // unordered_set
#include <bitset> // bitset
#include <cctype> // isupper, islower, isdigit, toupper, tolower
#include <iomanip>//setprecision
using namespace std;
int main(){
    double a,b=acos(-1);
    cin>>a;
    cout<<fixed<<setprecision(12)<<a*2*b;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:21:16: error: 'acos' was not declared in this scope
   21 |     double a,b=acos(-1);
      |                ^~~~
Language: C

import math
print(int(input()) * 2 * math.pi)

Compiler output:
main.c:1:1: error: unknown type name 'import'
    1 | import math
      | ^~~~~~
main.c:2:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'print'
    2 | print(int(input()) * 2 * math.pi)
      | ^~~~~
Language: C

#include <iostream>
using namespace std;

int main() {
	int R;
	cin >> R;
	//R = 73;
	cout << 2 * R * 3.141592653;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define REP(i,n) for(int i=0;i<(n);++i)
#define ALL(v)   (v).begin(),(v).end()
#define debug(x) cerr<<#x<<": "<<(x)<<endl
#define INF      (int)1e9
#define EPS      (double)1e-9
#define MOD      ((int)1e9+7)
using namespace std;
typedef long long     llong;
typedef vector<int>   vi;
typedef vector<vi >   vvi;
typedef vector<vvi >  vvvi;
typedef pair<int,int> pii;
template<class Type> void line(const Type &a){int cnt=0;for(const auto &elem:a){if(cnt++)cout<<' ';cout<<elem;}cout<<endl;}

int main(){
	double pi=acos(-1);
	
	int r;
	cin>>r;
	
	double ans=2*r*pi;
	printf("%.10f\n",ans);
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
#include<math.h>
using namespace std;

int main(){
	// sengen
	double r;
	// nyuryoku
	cin >> r;
	// keisan
	cout << (double)2*r*pi();
	// syutsuryoku
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#define PI 3.14159265359
int main()
{
  using namespace std;
  int R;
  double l;
  cin >> R;
  cout << 2 * PI * R;
  return 0;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#include <stdio.h>
#define PAI 3.14159265358979323846

int main(void)
{
  int r; // 半径R
  double enshu;
  
  scanf("%d", &r);
  
  enshu = 2.00 * PAI * r(double);
  
  printf("%f", enshu);
  
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:26: error: expected expression before 'double'
   11 |   enshu = 2.00 * PAI * r(double);
      |                          ^~~~~~
main.c:11:24: error: called object 'r' is not a function or function pointer
   11 |   enshu = 2.00 * PAI * r(double);
      |                        ^
main.c:6:7: note: declared here
    6 |   int r; // 半径R
      |       ^
Language: C

#include <bits/stdc++.h>
using namespace std;

int main()
{


int r;
cin >> r;
cout << 2 * r * 3.14159265359;






}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <stdio.h>
#include <iostream>
using namespace std;
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(), (x).end()
typedef long long ll;
const int INF (1<<30);

int main() {
  int R;
  cin >> R;

  double pi = 3.14159265;

  printf("%.10f\n", 2.0*pi*R);
  return 0;
}


Compiler output:
main.c:2:10: fatal error: iostream: No such file or directory
    2 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
#include<stdio.h>
#include<stdlib.h>

using namespace std;
#define endl "\n"
#define FILEIO freopen("input.txt", "r", stdin);freopen("output.txt", "w", stdout);
#define LL long long 
#define mod 1000000007LL
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define pb push_back
#define pp pop_back
//#define p push
#define I insert
#define bg begin()
#define ed end()
#define sz size()
#define all(v) v.begin(),v.end()
typedef vector<LL> vi;
typedef pair<int,int> ii;
typedef vector<ii> vii;
typedef map<LL ,LL > mii;
//typedef priority_queue<int> pq;
typedef queue<int>que;
typedef stack<int>stk;
#define Inf 100000005LL
#define f first
#define s second






int main(){

  
	  double n;
	  cin>>n;
	  cout<< 2 * 3.14*n;

   
}

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <cstdio>
#include <vector>
#include <cmath>

using namespace std;
using ll = long long;
using P = pair<int,int>;
#define rep(i,n) for (ll i = 0; i < (n); ++i)

int main() {
    double n;
    cin >> n;
    cout << fixed << n*(6.28318530717958623200) << endl;
    return 0;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C++

#include"bits/stdc++.h"
using namespace std;
typedef long long ll;


using Graph = vector<vector<int>>;//グラフ型
void dfs(const Graph& G, int v/*根*/, vector<bool>& seen) {
	seen[v] = true;  //vを訪問済にする
	for (auto next_v : G[v]) { //訪問済にしたvとつながっている場所を順番に探す
		if (seen[next_v]) continue; //もし探索済みならスルー
		dfs(G, next_v, seen); //再帰的に探索
	}
}

void bfs(const Graph& G, queue<int>& que/*発見したが訪問はしていない*/, vector<int>& dist/*開始地点からの距離*/) {

	while (!que.empty()) {
		int v = que.front();//queのうち先頭のものからスタート
		que.pop();//先頭を削除

		for (int nv : G[v]) {//vとつながっている点を列挙
			if (dist[nv] != -1) continue;//発見済(=距離が格納されている)であればスルー
			dist[nv] = dist[v] + 1;//vとつながっている点に距離の情報を追加
			que.push(nv);//vとつながっている点を発見済にする
		}
	}
}

template<typename T>
T gcd(T a, T b) {
	if (a % b == 0) {
		return(b);
	}
	else {
		return(gcd(b, a % b));
	}
}

template<typename T>
T lcm(T a, T b) {
	return a * b / gcd(a, b);
}


template<typename T>
bool same(T x_b, T x_e, T y_b, T y_e) {
	for (auto i = x_b, j = y_b; i != x_e && j != y_e; ++i, ++j) {
		if (*i != *j) {
			return false;
		}
	}
	return true;
}


int main(void) {
	double n;
	cin >> n;
	ans = n * 2 * acos(-1);
	cout << ans;
}

/*
9   3**2 1
27  3**3 2
81  3**4 3

11121213131415161516
3234566667

	
	*/


Compiler output:
a.cc: In function 'int main()':
a.cc:59:9: error: 'ans' was not declared in this scope; did you mean 'abs'?
   59 |         ans = n * 2 * acos(-1);
      |         ^~~
      |         abs
Language: C

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define make_pair mkp
int main()
{
	double r;
	cin>>r;
	printf("%.8f\n",r*3.14159265*2.0);
} 

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<iostream>
#include<string>
using namespace std;
int main()
{
	int r;
	float f = 3.141592;

	cin >> r;

	float ans = r * 2 * f;

	cout << ans << endl;

	return 0;
}

Compiler output:
main.c:1:9: fatal error: iostream: No such file or directory
    1 | #include<iostream>
      |         ^~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int inf=0x3f3f3f3f;
const int MOD=1e9+7;
const int maxn=1e5+10;
ll gcd(ll a, ll b){return (b==0)?a:gcd(b, a%b);}
bool isPrime(ll n){
    if(n<=3){
        return n>1;
    }
    if(n%6!=1&&n%6!=5){
        return false;
    }
    ll sqr=sqrt(n);
    for(ll i=5;i<=sqr;i+=6){
        if(n%i==0||n%(i+2)==0){
            return false;
        }
    }
    return true;
}
int dis[4][2]={0,1,0,-1,1,0,-1,0};
int read(){
    int x=0,f=1;char c=getchar();
    while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}
    while (c>='0'&&c<='9') x=(x<<1)+(x<<3)+(c^48),c=getchar();
    return x*f;
}


int main()
{
	int n;cin>>n;
	float pi=3.1415926535898;
	printf("%lf\n",pi*2*n);
}
 

Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <cstdint>
#include <cmath>
#include <string>
#include <vector>
#include <map>
#include <algorithm>

int main(void)
{
    int64_t R;

    std::cin >> R;

    std::cout << (double)(2*M_PI*R) << std::endl;

    return 0;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.
Language: C

#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define all(a) a.begin(),a.end()
#define eb emplace_back
#define lb(v,k) (lower_bound(all(v),k)-v.begin())
#define ub(v,k) (upper_bound(all(v),k)-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
using ll=long long;
using P=pair<ll,ll>;
using PP=tuple<ll,ll,ll>;
using S=multiset<ll>;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
const ll inf=1001001001001001;
const int INF=1001001001;
const int mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
void decimal(int x){cout<<fixed<<setprecision(x);}
ll GCD(ll a,ll b){if(b==0) return a; return GCD(b,a%b);}
ll LCM(ll a,ll b){return(a/GCD(a,b))*(b/GCD(a,b))*GCD(a,b);}
ll POW(ll a,ll b){a%=mod;if(b==0)return 1;if(b&1)return a*POW(a,b-1)%mod;ll k=POW(a,b/2);return k*k%mod;}
vi calc(ll x){vi res;while(x>0){res.eb(x%10);x/=10;}reverse(all(res));return res;}

void solve() {
  int r;
  cin>>r;
  double ans=2*pi*r;
  decimal(10);
  out(ans);
}

signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
}


Compiler output:
main.c:2:10: fatal error: bits/stdc++.h: No such file or directory
    2 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

#define rep0(i, n) for(ll i=0; i<(ll)(n); i++)
#define rep1(i, n) for(ll i=1; i<=(ll)(n); i++)
#define rep(i, a, b) for(ll i=(ll)a; i<=(ll)(b); i++)
#define rep0r(i, n) for(ll i=(ll)(n)-1; i>=0; i--)
#define rep1r(i, n) for(ll i=(ll)(n); i>0; i--)
#define repr(i, a, b) for(ll i=(ll)b; i>=(ll)(a); i--)
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) a * b / __gcd(a, b)


void solve() {
    double r;
    double pi = 3.14159265358979;
    
    cin >> r;

    cout << 2 * pi * r << '\n';
}

signed main() {
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    solve();
    return 0;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include<bits/stdc++.h>
using namespace std;

int main() {
  double pai = 3.14159265358979323846264338327950288;
  int r;
  cin >> r;
  cout << (double)r * 2 * pai << endl;
    
}


Compiler output:
main.c:1:9: fatal error: bits/stdc++.h: No such file or directory
    1 | #include<bits/stdc++.h>
      |         ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define all(x) (x).begin(),(x).end()
using namespace std;
using ll = long long;
using P = pair<int,int>;
template <class T> void chmin(T &a, const T &b) noexcept { if (b < a) a = b; }
template <class T> void chmax(T &a, const T &b) noexcept { if (a < b) a = b; }
void debug_out() { cout << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) { cout << H << " "; debug_out(T...); }
#ifdef _DEBUG
  #define debug(...) debug_out(__VA_ARGS__)
#else
  #define debug(...) 
#endif

int main() {
  std::cin.tie(nullptr);
  std::ios_base::sync_with_stdio(false);
  std::cout << std::fixed << std::setprecision(15);
  double r;
  cin >> r;
  double ans = 2*M_PI*r;
  cout << ans << endl;
  return 0;
}

Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include <bits/stdc++.h>
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include "bits/stdc++.h"

using namespace std;

#define rep(loop, N) for (int loop = 0; loop < N; loop++)

struct Node {
	Node* parent = NULL;
	vector<Node*> child;
	long long value = 0;
};
struct Edge {
	int parent = 0;
	int child = 0;
	bool operator <(const Edge& right) const { return parent < right.parent; }
};
struct Tree {
	vector<Node> node;
	Tree(int, vector<Edge>);
};
Tree::Tree(int nodeNum, vector<Edge> edge) {
	node.resize(nodeNum);
	for (Edge& it : edge) {
		node[it.child].parent = &node[it.parent];
		node[it.parent].child.push_back(&node[it.child]);
	}
}

map<long long, int> factorization(long long N) {
	map<long long, int> re;
	while (true) {
		if (N % 2 == 0) {
			N /= 2;
			re[2]++;
			if (N == 1) break;
		}
		else {
			break;
		}
	}
	for (int loop = 3; (long long)loop * (long long)loop <= N; loop += 2) {
		if (N % loop == 0) {
			N /= loop;
			re[loop]++;
			loop -= 2;
			if (N == 1) break;
		}
	}
	if (N > 1) re[N]++;
	return re;
}

struct Memo {
	long long fact = 0;
	long long fact_inv = 0;
	long long inv = 0;
};
class Combination1 {
private:
	long long m_module = 1000000007;
	vector<struct Memo> memo;
public:
	long long calculate(int, int);
	Combination1(int, long long);
};
long long Combination1::calculate(int n, int k) {
	return ((memo[n].fact * memo[k].fact_inv) % m_module * memo[n - k].fact_inv) % m_module;
}
Combination1::Combination1(int memo_max, long long module = 1000000007) {
	m_module = module;
	memo.push_back({ 1,1,0 });
	memo.push_back({ 1,1,1 });
	for (int loop = 2; loop <= memo_max; loop++) {
		struct Memo temp;
		temp.fact = (memo[loop - 1].fact * loop) % m_module;
		temp.inv = m_module - (memo[m_module % loop].inv * int(m_module / loop)) % m_module;
		temp.fact_inv = (memo[loop - 1].fact_inv * temp.inv) % m_module;
		memo.push_back(temp);
	}
}

class Combination2 {
private:
	int size = 0;
	bool add(int);
public:
	vector<int> sequence;
	bool next_combination(void);
	Combination2(int, int);
};
bool Combination2::add(int index) {
	if (index == (int)sequence.size() - 1 && sequence[index] == size - 1
		|| index < (int)sequence.size() - 1 && sequence[index] == sequence[index + 1] - 1) {
		if (index == 0) {
			return false;
		}
		else {
			bool re = add(index - 1);
			sequence[index] = sequence[index - 1] + 1;
			return re;
		}
	}
	else {
		sequence[index]++;
		return true;
	}
}
bool Combination2::next_combination(void) {
	return (sequence.size() == 0) ? false : add(sequence.size() - 1);
}
Combination2::Combination2(int n, int r) {
	size = n;
	for (int loop = 0; loop < r; loop++) sequence.push_back(loop);
	return;
}

void A_Circle_Pond(void) {

	double R; cin >> R;

	cout << R * 2.0 * 3.141592 << endl;
	return;
}

int main(void) {

	A_Circle_Pond();
	return 0;
}


Compiler output:
main.c:1:10: fatal error: bits/stdc++.h: No such file or directory
    1 | #include "bits/stdc++.h"
      |          ^~~~~~~~~~~~~~~
compilation terminated.
Language: C

#include <iostream>
#include <string>
#include <set>
#include <algorithm>
#include <cstdio>
#include <vector>
#include <map>
#include <cstring>
#include <math.h>
using namespace std;
#define MAXA 1001
#define MAXB 1001
#define MAXH 1000000001
#define MAXW 405
#define INF 5000
#define MAXN 100001
#define MAXM 1001
#define MAXP 1000001
#define MOD 1000000007
#define EPS (1e-10)
typedef long long ll;
typedef pair<ll, ll> P;
ll N, A, B;

P max_element(ll n){
    ll ele = 1;
    ll lim = (ll)sqrt(n);
    for(ll i = 1;i <= lim;i++){
        if(!(n % i)){
            ele = i;
        }
    }
    P res = {ele, n / ele};
    return res;
}

int digitnum(ll n){
    int res = 1;
    while(n / 10){
        res++;
        n /= 10;
    }

    return res;
}


int main(){
    cin >> N;
    printf("%lf\n", N * M_PI);
    return 0;
}

Compiler output:
main.c:1:10: fatal error: iostream: No such file or directory
    1 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.