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

int main(){
    int n;
    cin >> n;
    int cnt = 0;
    
    for (int i=1; i<n; i++){
        int note = to_string(i);
        if ( note.size()%2!=0 ){
            cnt += 1; 
        }
    }
    cout << cnt << endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:3:5: error: 'cin' was not declared in this scope
    3 |     cin >> n;
      |     ^~~
a.cc:7:20: error: 'to_string' was not declared in this scope
    7 |         int note = to_string(i);
      |                    ^~~~~~~~~
a.cc:8:19: error: request for member 'size' in 'note', which is of non-class type 'int'
    8 |         if ( note.size()%2!=0 ){
      |                   ^~~~
a.cc:12:5: error: 'cout' was not declared in this scope
   12 |     cout << cnt << endl;
      |     ^~~~
a.cc:12:20: error: 'endl' was not declared in this scope
   12 |     cout << cnt << endl;
      |                    ^~~~
Language: C++

#include <iostream>
using namespace std;

int main(){
    int n;
    cin >> n;
    int cnt = 0;
    for (int i=1; i<n; i++){
        note = (str)i;
        if (　note.size()%2!=0　){
            cnt += 1; 
        }
    }
    cout << cnt << endl;
}

Compiler output:
a.cc:10:13: error: extended character 　 is not valid in an identifier
   10 |         if (　note.size()%2!=0　){
      |             ^
a.cc:10:30: error: extended character 　 is not valid in an identifier
   10 |         if (　note.size()%2!=0　){
      |                              ^
a.cc: In function 'int main()':
a.cc:9:9: error: 'note' was not declared in this scope
    9 |         note = (str)i;
      |         ^~~~
a.cc:9:17: error: 'str' was not declared in this scope; did you mean 'std'?
    9 |         note = (str)i;
      |                 ^~~
      |                 std
a.cc:10:13: error: '\U00003000note' was not declared in this scope
   10 |         if (　note.size()%2!=0　){
      |             ^~~~~~
a.cc:10:30: error: unable to find numeric literal operator 'operator""\U00003000'
   10 |         if (　note.size()%2!=0　){
      |                              ^~~
Language: C++

#include<bits/stdc++.h>
#define lld long long int
#define vec vector<lld>
#define pll pair<lld,lld>
#define pb push_back
#define ss second
#define ff first
#define mp make_pair
#define mod 1000000007
#define answer cout<<endl<<"answer : ";
#define maxn 100005
#define messi ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
using namespace std;
lld fuck(lld x);
{
    lld cnt=0;
    while(x>0)
    {
        x=x/10;
        cnt++;
    }
    return cnt;
}
int main() {messi lld t=1;//cin>>t;
    while(t--)
    {
        lld n=0,m=0,k=0,i=0,j=0,p=0,q=0,x=0,y=0,z=0,ans=0,cnt=0;string s;bool flag=false;
        cin>>n;
        for(i=1;i<=n;i++)
        {
            x=fuck(i);
            if(x%2==1)
                ans++;
        }
        cout<<ans<<endl;

    }
	return 0;
}
/*  CODED BY:-
 ________________________________________
|            __        __                |
|  /\   /\  |__)  /\  |  \ |__| \ /  /\  |
| /~~\ /~~\ |  \ /~~\ |__/ |  |  |  /~~\ |
|________________________________________|

*/


Compiler output:
a.cc:15:1: error: expected unqualified-id before '{' token
   15 | {
      | ^
Language: C++

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

int main(){
  int n;
  string s=to_string(n);
  int i;
  if(s.length()%2==0){i=s.length()-1;}
  else{i=s.length()-2;}
  int rrr=1,ans;
  int j=1;
  while(j<=i){
    rrr=rrr*81;
    ans+=rrr;
    j+=2;
  }
  int kkk=1;
  for(int k=0;k<s.length()-2;k++)
    kkk*10;
  ans+=n-kkk+1
}
  

Compiler output:
a.cc: In function 'int main()':
a.cc:20:15: error: expected ';' before '}' token
   20 |   ans+=n-kkk+1
      |               ^
      |               ;
   21 | }
      | ~
Language: C++

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

int main(){
  int n;
  string s=to_string(n);
  int i;
  if(s.length()%2==0){i=s.length()-1}
  else{i=s.length()-2}
  int rrr=1,ans;
  int j=1;
  while(j<=i){
    rrr=rrr*81;
    ans+=rrr;
    j+=2;
  }
  cout<<ans<<endl;
}
  

Compiler output:
a.cc: In function 'int main()':
a.cc:8:37: error: expected ';' before '}' token
    8 |   if(s.length()%2==0){i=s.length()-1}
      |                                     ^
      |                                     ;
a.cc:9:22: error: expected ';' before '}' token
    9 |   else{i=s.length()-2}
      |                      ^
      |                      ;
Language: Java

import java.util.Scanner;

public class Main096 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int ans = 0;
        for(int i=1; i<=n; i++) {
            int nn = Integer.toString(i).length();
            if(nn % 2 != 0) ans++;
        }
        System.out.println(ans);
    }
}

Compiler output:
Main.java:3: error: class Main096 is public, should be declared in a file named Main096.java
public class Main096 {
       ^
1 error
Language: C++

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

int power(int a, int n) {
    int res = 1;
    while (n > 0) {
        if (n & 1) res = res * a;
        a = a * a;
        n >>= 1;
    }
    return res;
}

int keta(int N) {
  int j;
  for (int i = 1; i <= 7; i++) {
    if (N >= power(10,i) && N < power(10,i+1)) {
      j = i + 1;
      break;
    }
  }
  return j;
}
    

int main() {
  int N;
  cin >> N;
  int cnt = 0;
  for(int i = 1; i <= N; i++) {
    if (keta(i) % 2 == 1) cnt++;
  }
  cout << cnt << endl;
}


Compiler output:
a.cc:1:2: error: invalid preprocessing directive #inculude; did you mean #include?
    1 | #inculude <bits/stdc++.h>
      |  ^~~~~~~~
      |  include
a.cc: In function 'int main()':
a.cc:28:3: error: 'cin' was not declared in this scope
   28 |   cin >> N;
      |   ^~~
a.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | #inculude <bits/stdc++.h>
a.cc:33:3: error: 'cout' was not declared in this scope
   33 |   cout << cnt << endl;
      |   ^~~~
a.cc:33:3: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:33:18: error: 'endl' was not declared in this scope
   33 |   cout << cnt << endl;
      |                  ^~~~
a.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
  +++ |+#include <ostream>
    1 | #inculude <bits/stdc++.h>
Language: C++

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

int power(int a, int n) {
    int res = 1;
    while (n > 0) {
        if (n & 1) res = res * a;
        a = a * a;
        n >>= 1;
    }
    return res;
}

int keta(int N) {
  int j;
  for (int i = 1; i <= 7; i++) {
    if (N >= power(10,i)) {
      j = i + 1;
      break;
    }
  }
  return j;
}
    

int main() {
  int N;
  cin >> N;
  int cnt = 0;
  for(int i = 1; i <= N; i++) {
    if (keta(i) % 2 == 1) cnt++;
  }
  cout << cnt << endl;
}

Compiler output:
a.cc:1:2: error: invalid preprocessing directive #inculude; did you mean #include?
    1 | #inculude <bits/stdc++.h>
      |  ^~~~~~~~
      |  include
a.cc: In function 'int main()':
a.cc:28:3: error: 'cin' was not declared in this scope
   28 |   cin >> N;
      |   ^~~
a.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | #inculude <bits/stdc++.h>
a.cc:33:3: error: 'cout' was not declared in this scope
   33 |   cout << cnt << endl;
      |   ^~~~
a.cc:33:3: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:33:18: error: 'endl' was not declared in this scope
   33 |   cout << cnt << endl;
      |                  ^~~~
a.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
  +++ |+#include <ostream>
    1 | #inculude <bits/stdc++.h>
Language: C++

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

bool digitsodd(int x){
  int count=0;
  while(x>0){
    x/=10;
    count++;
  }
  return count%2!=0
}

int main() {
  int N;
  cin >> N;
  int count=0;
  for(int i=1;i<=N;i++){
    if(digitsodd(i)) count++;
  }
  cout << count << endl;
}

Compiler output:
a.cc: In function 'bool digitsodd(int)':
a.cc:10:20: error: expected ';' before '}' token
   10 |   return count%2!=0
      |                    ^
      |                    ;
   11 | }
      | ~
Language: C++

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

int main(){
  int N;
  cin >> N;
  int ans;
  for(int i=0;i<N;i++){
    if(i.size()%2==1){
      ans+=1;
    }
  }
  cout << ans << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:9:10: error: request for member 'size' in 'i', which is of non-class type 'int'
    9 |     if(i.size()%2==1){
      |          ^~~~
Language: C++

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

int main(){
  int N;
  cin >> N;
  int ans;
  for(int i=0;i<N;i++){
    if(i.size()%2==1){
      ans+=1;
    }
  }
  cout << ans << endl;
}

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

import java.util.Scanner;
public class Uneven_Numbers2 {

	public static void main(String[] args) {

        Scanner s = new Scanner(System.in);
	    int N = s.nextInt();
	    int anser = 0;
	    for(int i=1; i<N+1; i++) {
	    	if(String.valueOf(i).length() %2 == 1) {
	    		anser++;
	    		
	    	}
	    }
	    
	    System.out.println(anser);
		
	}
}


Compiler output:
Main.java:2: error: class Uneven_Numbers2 is public, should be declared in a file named Uneven_Numbers2.java
public class Uneven_Numbers2 {
       ^
1 error
Language: C++

#include<bits/stdc++.h>
using namespace std;
int main()
{
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
    int b=0,c,e=1,f=0,a,k=0,l;
    cin>>a;
    for(int i=a;i>0;i=i/10)
        b++;
    if(b>2)
    for(int k=b;k>1;k=k-2)
        f=f+9*e;e=e*100;
    else if(b==1)
        f=a;
    if(b%2!=0 && b>2)
        f=f+a%100+1;
    if(b==2)
        f=9;
    cout<<f;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:13:5: error: 'else' without a previous 'if'
   13 |     else if(b==1)
      |     ^~~~
Language: C++

#include<iostream>
#include<vector>
#include<set>
#include<algorithm>

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

int main(){

    ll n; cin >> n;
    int cnt=0;

    rep(i,n){
        string s= to_string(i)
        
    }

     return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:18:5: error: expected ',' or ';' before '}' token
   18 |     }
      |     ^
Language: C++

#include<bits/stdc++.h>
#define ll long long int
#define pii <pair<ll,ll>>
using namespace std;

digit_number(ll p)
{
    ll c=0;
    while(p>0)
    {
        c++;
        p=p/10;
    }
    return c;
}

solve()
{
    ll n;
     cin >> n;
     ll ans=0;
     for(int i=1;i<=n;i++)
     {
         if(digit_number(i)%2!=0)
            ans++;
     }
     cout << ans << endl;
}

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


Compiler output:
a.cc:6:1: error: ISO C++ forbids declaration of 'digit_number' with no type [-fpermissive]
    6 | digit_number(ll p)
      | ^~~~~~~~~~~~
a.cc:17:1: error: ISO C++ forbids declaration of 'solve' with no type [-fpermissive]
   17 | solve()
      | ^~~~~
a.cc: In function 'int solve()':
a.cc:28:1: warning: no return statement in function returning non-void [-Wreturn-type]
   28 | }
      | ^
Language: C++

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

int main(){
  long long N;
  cin >> N;
  if(N<=9){
    cout << i << endl;
  }
  else if(N<=99){
    cout << 9 << endl;
  }
  else if(N<=999){
    cout << N-90 << endl;
  }
  else if(N<=9999){
    cout << 909 << endl;
  }
  else if(N<=99999){
    cout << N-9090 << endl;
  }
  else if(N<=999999){
    cout << 90909 << endl;
  }
}
    
  

Compiler output:
a.cc: In function 'int main()':
a.cc:8:13: error: 'i' was not declared in this scope
    8 |     cout << i << endl;
      |             ^
Language: C

#include<stdio.h>
int main(void){

  int N=0,len=0,count=0;
  scanf("%d",&N);
  str[100001]={0};
  
  for(i=0;i<N;i++){
    scanf("%s",str);
    len=strlen(str);
  	if(len%2 == 1){
    	count++;
    }
  }
  
  printf("%d",count);

 return 0;
}

Compiler output:
main.c: In function 'main':
main.c:6:3: error: 'str' undeclared (first use in this function)
    6 |   str[100001]={0};
      |   ^~~
main.c:6:3: note: each undeclared identifier is reported only once for each function it appears in
main.c:6:15: error: expected expression before '{' token
    6 |   str[100001]={0};
      |               ^
main.c:8:7: error: 'i' undeclared (first use in this function)
    8 |   for(i=0;i<N;i++){
      |       ^
main.c:10:9: error: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
   10 |     len=strlen(str);
      |         ^~~~~~
main.c:2:1: note: include '<string.h>' or provide a declaration of 'strlen'
    1 | #include<stdio.h>
  +++ |+#include <string.h>
    2 | int main(void){
main.c:10:9: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
   10 |     len=strlen(str);
      |         ^~~~~~
main.c:10:9: note: include '<string.h>' or provide a declaration of 'strlen'
Language: C++

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

bool f(int x){
  int keta=0;
  while(x){
    x/=10;
    keta++;
  }
  return keta%2!==1;
}

int main(){
  int n,num=0;
  cin>>n;
  for(int i=1;i<=n;i++){
    if(f(i)){
      num++;
    }
  }
  cout<<num<<endl;
}


Compiler output:
a.cc: In function 'bool f(int)':
a.cc:10:18: error: expected primary-expression before '=' token
   10 |   return keta%2!==1;
      |                  ^
Language: C++

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

bool f(int x){
  int keta=0;
  while(x){
    x/=10;
    keta++;
  }
  if(keta) f(x)=true;
}

int main(){
  int n,num=0;
  cin>>n;
  for(int i=1;i<=n;i++){
    if(f(i)){
      num++;
    }
  }
  cout<<num<<endl;
}


Compiler output:
a.cc: In function 'bool f(int)':
a.cc:10:13: error: lvalue required as left operand of assignment
   10 |   if(keta) f(x)=true;
      |            ~^~~
a.cc:11:1: warning: no return statement in function returning non-void [-Wreturn-type]
   11 | }
      | ^
Language: C++

#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#define ll long long
using namespace std;

const ll mod = 1e9 + 7;

ll C[2005][2005];
ll dp[100005][13];

int main(){
    int A,B,N,a = 1,ans++;;
    cin >> N;
    while(a <= N){
        if(10 > a || (1000 > a && a >= 100) || (100000 > a && a >=10000) )ans ++;
        a++;
    }
    cout << ans << endl;
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:14:24: error: expected initializer before '++' token
   14 |     int A,B,N,a = 1,ans++;;
      |                        ^~
a.cc:17:75: error: 'ans' was not declared in this scope; did you mean 'abs'?
   17 |         if(10 > a || (1000 > a && a >= 100) || (100000 > a && a >=10000) )ans ++;
      |                                                                           ^~~
      |                                                                           abs
a.cc:20:13: error: 'ans' was not declared in this scope; did you mean 'abs'?
   20 |     cout << ans << endl;
      |             ^~~
      |             abs
Language: C++

#include<bits/stdc++.h>
using namespace stdl
  
 int main(){
  int n,ma=0;
  cin>>n;
  for(int i=1;i<=n;i++){
    int nu=0;
    while(i>0){
      i/10;
      nu++;
    }
    if(nu%2!=0){
      ma++;
    }
  }
  cout<<ma<<endl;
}
  
  

Compiler output:
a.cc:2:17: error: 'stdl' is not a namespace-name
    2 | using namespace stdl
      |                 ^~~~
a.cc:2:21: error: expected ';' before 'int'
    2 | using namespace stdl
      |                     ^
      |                     ;
    3 | 
    4 |  int main(){
      |  ~~~                 
a.cc: In function 'int main()':
a.cc:6:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    6 |   cin>>n;
      |   ^~~
      |   std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146,
                 from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:17:3: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   17 |   cout<<ma<<endl;
      |   ^~~~
      |   std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:17:13: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   17 |   cout<<ma<<endl;
      |             ^~~~
      |             std::endl
In file included from /usr/include/c++/14/istream:41,
                 from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
Language: C++

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
  string a;
  int ans=0;
  cin>>a;
  int n=atoi(a);
 

  for(int i=1;i<=n;i++){
    string st=to_string(i);
    int k=st.length();
    if(k%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:9:14: error: cannot convert 'std::string' {aka 'std::__cxx11::basic_string<char>'} to 'const char*'
    9 |   int n=atoi(a);
      |              ^
      |              |
      |              std::string {aka std::__cxx11::basic_string<char>}
In file included from /usr/include/c++/14/cstdlib:79,
                 from /usr/include/c++/14/ext/string_conversions.h:43,
                 from /usr/include/c++/14/bits/basic_string.h:4154,
                 from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/stdlib.h:105:30: note:   initializing argument 1 of 'int atoi(const char*)'
  105 | extern int atoi (const char *__nptr)
      |                  ~~~~~~~~~~~~^~~~~~
Language: C++

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

int main() {
  int n;
  cin>>n;
  int ans;
  for(int i=1;i<=n;i++){
    if(i<10 || (100<=i && i<1000)||(10000<=i&&i<100000)){ 
    ans++;
  }
  cout<<ans<<endl;
}




 





Compiler output:
a.cc: In function 'int main()':
a.cc:14:2: error: expected '}' at end of input
   14 | }
      |  ^
a.cc:5:12: note: to match this '{'
    5 | int main() {
      |            ^
Language: C++

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

int main(){
  int num=0;
  string n;
  cin>>n;
  for(string i=1;i<=n;i++){
    if(i.size()%2!=0){
      num++;
    }
  }
  cout<<num<<endl;
}
    


Compiler output:
a.cc: In function 'int main()':
a.cc:8:16: error: conversion from 'int' to non-scalar type 'std::string' {aka 'std::__cxx11::basic_string<char>'} requested
    8 |   for(string i=1;i<=n;i++){
      |                ^
a.cc:8:24: error: no 'operator++(int)' declared for postfix '++' [-fpermissive]
    8 |   for(string i=1;i<=n;i++){
      |                       ~^~
Language: C++

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

int main(){
  int n,num=0;
  cin>>n;
  for(int i=1;i<=n;i++){
    if(str(i).size()%2!=0){
      num++;
    }
  }
  cout<<num<<endl;
}
    


Compiler output:
a.cc: In function 'int main()':
a.cc:8:8: error: 'str' was not declared in this scope; did you mean 'std'?
    8 |     if(str(i).size()%2!=0){
      |        ^~~
      |        std
Language: C++

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

int main(){
  int n,num=0;
  cin>>n;
  for(int i=1;i<=n;i++){
    if((string)i.size()%2!=0){
      num++;
    }
  }
  cout<<num<<endl;
}
    

Compiler output:
a.cc: In function 'int main()':
a.cc:8:18: error: request for member 'size' in 'i', which is of non-class type 'int'
    8 |     if((string)i.size()%2!=0){
      |                  ^~~~
Language: C++

#include "bits/stdc++.h"

using namespace std;

using ll = long long;

template<typename T> using V = std::vector<T>;
using Vi = V<int>;
using VVi = V<V<int>>;
using Vl = V<ll>;
using VVl = V<V<ll>>;
using Vs = V<string>;

template<typename T1, typename T2> using P = std::pair<T1, T2>;
using Pii = P<int, int>;
using Pll = P<ll, ll>;
using Pdd = P<double, double>;

template<typename T1, typename T2> using M = std::map<T1, T2>;
using Mii = M<int, int>;
using Mll = M<ll, ll>;
using Msi = M<string, int>;

#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define REP2(i,s,e) for(int i=(int)(s);i<(int)(e);++i)
#define RREP(i,s,e) for(int i=(int)(s);i>=(int)(e);--i)
#define FOR(i,c) for(__typeof((c).begin())i=(c).begin(),ie=(c).end();i!=ie;++i)
#define RFOR(i,c) for(__typeof((c).rbegin())i=(c).rbegin(),ie=(c).rend();i!=ie;++i)
#define ALL(c) (c).begin(), (c).end()

const double PI = acos(-1);
const ll MOD = 1e9+7;

int n;

int main() {
    cin >> n;
    int c = 0;
    REP2(i, 1, n+1) {
        if (to_string(i).length % 2 == 1) {
            c++;
        }
    }
    cout << c << '\n';

    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:40:26: error: invalid use of member function 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size_type std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::length() const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; size_type = long unsigned int]' (did you forget the '()' ?)
   40 |         if (to_string(i).length % 2 == 1) {
      |             ~~~~~~~~~~~~~^~~~~~
      |                                ()
Language: C++

#include <iostream>
#include <string>
using namespace std;

double GetDigit(int num){
    return log10(num)+1;
}

int main() {
  int n;
  cin >> n;
  int ans = 0;
  for(int i = 0; i <= n; i++) {
    if(GetDigit(i) % 2 == 1) {
      ans++;
    }
  }
  cout << ans << endl;
  return 0;
}


Compiler output:
a.cc: In function 'double GetDigit(int)':
a.cc:6:12: error: 'log10' was not declared in this scope
    6 |     return log10(num)+1;
      |            ^~~~~
a.cc: In function 'int main()':
a.cc:14:20: error: invalid operands of types 'double' and 'int' to binary 'operator%'
   14 |     if(GetDigit(i) % 2 == 1) {
      |        ~~~~~~~~~~~ ^ ~
      |                |     |
      |                |     int
      |                double
Language: C++

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

int main(){
  int n;
  cin>>n;
  if(n>=100000)
    cout<<90909;
  else if(n>=10000)
    cout<<n-9090;
  else if(n>=1000)
    cout<<909<<endl;
  else if(n>=100)
    cout<<n-90<<endl;;
  else if(n>=10)
    cout<<9<<endl;
  else
    cout<<n<<endl;
    
    
  
    
}

Compiler output:
a.cc: In function 'int main()':
a.cc:20:3: error: 'else' without a previous 'if'
   20 |   else if(n>=10)
      |   ^~~~
Language: C++

#include <iostream>
#include <string>
using namespace std;

int GetDigit(int num){
    return log10(num)+1;
}

int main() {
  int n;
  cin >> n;
  int ans = 0;
  for(int i = 0; i <= n; i++) {
    if(GetDigit(i) % 2 == 1) {
      ans++;
    }
  }
  cout << ans << endl;
  return 0;
}


Compiler output:
a.cc: In function 'int GetDigit(int)':
a.cc:6:12: error: 'log10' was not declared in this scope
    6 |     return log10(num)+1;
      |            ^~~~~
Language: C++

def ketasuu(n):
    ans  = 0
    while (n >= 1):
        n = n/10
        ans += 1
    return ans

n = int(input())

k = ketasuu(n)
ans = 0
for i in range(1,k,2):
    ans += 10**i-10**(i-1)
if (k%2 == 1):
    ans += n-10**(k-1)+1

print(ans)




Compiler output:
a.cc:1:1: error: 'def' does not name a type
    1 | def ketasuu(n):
      | ^~~
Language: C++


#include <iostream>
#include <numeric>
#include <stdio.h>
#include <iomanip>
#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
using namespace std;
using ll = long long;
#define rep(i, n) for (long long i = 0; i < (long long)(n); i++)
int Max(int(a), int(b), int(c)) {
	return max(max(a, b), c);
}
int Min(int(a), int(b), int(c)) {
	return min(min(a, b), c);
}





int main() {
	int N,an=0;
	cin >> N;
	rep(i, N) {
		if (ll(log10(i+1))%2==0) {
			an++;;
		}
	}
	
		cout << an << endl;
	
	
}

Compiler output:
a.cc: In function 'int main()':
a.cc:40:24: error: 'log10' was not declared in this scope
   40 |                 if (ll(log10(i+1))%2==0) {
      |                        ^~~~~
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      { 
      if(len(str[i])%2==1);
      }
  printf("%d",count);
  
  return 0;
  }


Compiler output:
main.c: In function 'main':
main.c:10:10: error: implicit declaration of function 'len' [-Wimplicit-function-declaration]
   10 |       if(len(str[i])%2==1);
      |          ^~~
Language: C++

#include <bits/stdc++.h>
using namespace std;
int digits(int x){
  int sum=0;
  while(x>0) {
    x/=10;
    sum++;
  }
  return sum;
}
int main() {
  int n;
  cin >> n;
  ans=0;
  for(int i=1;i<=n;++i) {
    if(digits(i)%2!=0) ans++;
  }
  cout << ans << endl;
  return 0;
}
    

Compiler output:
a.cc: In function 'int main()':
a.cc:14:3: error: 'ans' was not declared in this scope; did you mean 'abs'?
   14 |   ans=0;
      |   ^~~
      |   abs
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      if(len(str[i])%2==1);
  return 0;
  }


Compiler output:
main.c: In function 'main':
main.c:9:10: error: implicit declaration of function 'len' [-Wimplicit-function-declaration]
    9 |       if(len(str[i])%2==1);
      |          ^~~
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      if(len(str[i])%2=1);
  return 0;
  }


Compiler output:
main.c: In function 'main':
main.c:9:10: error: implicit declaration of function 'len' [-Wimplicit-function-declaration]
    9 |       if(len(str[i])%2=1);
      |          ^~~
main.c:9:23: error: lvalue required as left operand of assignment
    9 |       if(len(str[i])%2=1);
      |                       ^
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      if((strlen(str[i]))%2=1);
  return 0;
  }


Compiler output:
main.c: In function 'main':
main.c:9:21: error: passing argument 1 of 'strlen' makes pointer from integer without a cast [-Wint-conversion]
    9 |       if((strlen(str[i]))%2=1);
      |                  ~~~^~~
      |                     |
      |                     char
In file included from main.c:2:
/usr/include/string.h:407:35: note: expected 'const char *' but argument is of type 'char'
  407 | extern size_t strlen (const char *__s)
      |                       ~~~~~~~~~~~~^~~
main.c:9:28: error: lvalue required as left operand of assignment
    9 |       if((strlen(str[i]))%2=1);
      |                            ^
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      if(strlen(str[i])%2=1);
  return 0;
  }


Compiler output:
main.c: In function 'main':
main.c:9:20: error: passing argument 1 of 'strlen' makes pointer from integer without a cast [-Wint-conversion]
    9 |       if(strlen(str[i])%2=1);
      |                 ~~~^~~
      |                    |
      |                    char
In file included from main.c:2:
/usr/include/string.h:407:35: note: expected 'const char *' but argument is of type 'char'
  407 | extern size_t strlen (const char *__s)
      |                       ~~~~~~~~~~~~^~~
main.c:9:26: error: lvalue required as left operand of assignment
    9 |       if(strlen(str[i])%2=1);
      |                          ^
Language: C

#include<stdio.h>
#include<string.h>
int main()
  { 
    int n,i,count=0;
    scanf("%d",&n);
    char str[100000];
    for(i=1;i<=(n+1);count++)
      if(len(str[i])%2=1);
  return 0;
  }

Compiler output:
main.c: In function 'main':
main.c:9:10: error: implicit declaration of function 'len' [-Wimplicit-function-declaration]
    9 |       if(len(str[i])%2=1);
      |          ^~~
main.c:9:23: error: lvalue required as left operand of assignment
    9 |       if(len(str[i])%2=1);
      |                       ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
bool f(int x){
  int keta=0;
  while(x){
    keta++;
    x/=10;
  }
  if(keta%2==1) return true;
  return false;
}
int main(){
  int n;
  cin>>n;
  int count=0;
  for(int i=1;i<=n;i++){
    if(f(x)) count++;
  }
  cout<<count<<endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:17:10: error: 'x' was not declared in this scope
   17 |     if(f(x)) count++;
      |          ^
Language: C++

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

int main(){
    int n; cin>>n;
    for(int i=0;i<=n;i++){
        if(to_string(i).length()%2==1) ans++;
    }
    cout<<ans<<endl;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:10:40: error: 'ans' was not declared in this scope; did you mean 'abs'?
   10 |         if(to_string(i).length()%2==1) ans++;
      |                                        ^~~
      |                                        abs
a.cc:12:11: error: 'ans' was not declared in this scope; did you mean 'abs'?
   12 |     cout<<ans<<endl;
      |           ^~~
      |           abs
Language: C++

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

int main() 
{ 
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    ll n, count = 0;
    cin >> n;
    for(int l = 1; l <= floor(log10(n)) + 1; l++) {
        if(l&1 && l == floor(log10(n)) + 1) {
            count += n - power2(10, l-1) + (l-1 != 0 ? 1 : 0);
        } else if (l&1) {
            count += power2(10, l) - power2(10, l-1);
        }
    }
    cout << count << '\n';
    return 0; 
}

Compiler output:
a.cc: In function 'int main()':
a.cc:13:26: error: 'power2' was not declared in this scope; did you mean 'powf32'?
   13 |             count += n - power2(10, l-1) + (l-1 != 0 ? 1 : 0);
      |                          ^~~~~~
      |                          powf32
a.cc:15:22: error: 'power2' was not declared in this scope; did you mean 'powf32'?
   15 |             count += power2(10, l) - power2(10, l-1);
      |                      ^~~~~~
      |                      powf32
Language: C

#include<stdio.h>
#include<string.h>
int main()
{
	int i,c=0;
	long n;
	double m[100000];

	scanf("%ld",&n);
	sprintf(m,"%ld",n);
	for(i=0;i<n;i++)
		if(strlen(m[i])%2==1)
			c+=0;
	printf("%d",c);
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:10:17: error: passing argument 1 of 'sprintf' from incompatible pointer type [-Wincompatible-pointer-types]
   10 |         sprintf(m,"%ld",n);
      |                 ^
      |                 |
      |                 double *
In file included from main.c:1:
/usr/include/stdio.h:365:38: note: expected 'char * restrict' but argument is of type 'double *'
  365 | extern int sprintf (char *__restrict __s,
      |                     ~~~~~~~~~~~~~~~~~^~~
main.c:12:28: error: incompatible type for argument 1 of 'strlen'
   12 |                 if(strlen(m[i])%2==1)
      |                           ~^~~
      |                            |
      |                            double
In file included from main.c:2:
/usr/include/string.h:407:35: note: expected 'const char *' but argument is of type 'double'
  407 | extern size_t strlen (const char *__s)
      |                       ~~~~~~~~~~~~^~~
Language: C++

include<iostream>
#include<cstdlib>
template<typename T>
void fin(T const& t){ std::cout << t << std::endl; exit(0); }

int main() {
  int N; std::cin >> N;
  if(N < 10) fin(N);
  if(N < 100) fin(9);
  if(N < 1000) fin(N-90);
  if(N < 10000) fin(909);
  if(N < 100000) fin(N-9090);
  fin(90909);
  return 0;
}


Compiler output:
a.cc:1:1: error: 'include' does not name a type
    1 | include<iostream>
      | ^~~~~~~
a.cc: In function 'void fin(const T&)':
a.cc:4:28: error: 'cout' is not a member of 'std'
    4 | void fin(T const& t){ std::cout << t << std::endl; exit(0); }
      |                            ^~~~
a.cc:3:1: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
    2 | #include<cstdlib>
  +++ |+#include <iostream>
    3 | template<typename T>
a.cc:4:46: error: 'endl' is not a member of 'std'
    4 | void fin(T const& t){ std::cout << t << std::endl; exit(0); }
      |                                              ^~~~
a.cc:3:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
    2 | #include<cstdlib>
  +++ |+#include <ostream>
    3 | template<typename T>
a.cc: In function 'int main()':
a.cc:7:15: error: 'cin' is not a member of 'std'
    7 |   int N; std::cin >> N;
      |               ^~~
a.cc:7:15: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
Language: C++

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

int check_digits(int n) {
  int res = 0;
  while(n > 0) {
    res++;
    n /= 10;
  }
  return res;
}

int main() {
  int N;
  cin >> N;
  
  int ans = 0;
  for (int i = 0; i < N; i++) {
    if (check_digits(i) % 2) ans++;
  }
  
  cout << ans << endl;
  
}
  
  

Compiler output:
a.cc: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>

int check_digits(int N) {
  int res = 0;
  while(N > 0) {
    res++;
    N /= 10;
  }
  return res;
}

int main() {
  int N;
  cin >> N;
  
  int ans = 0;
  for (int i = 0; i < N ;i++) {
    if (check_digits(i) % 2) ans++;
  }
  
  cout << ans << endl;
  
}
  
  

Compiler output:
a.cc: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 N;
    cin >> N;
    int keta = 0;
    int ans = 0;
    while (N == 0){
      N/10;
      keta++;
    }
    int M = keta+1;
    int K = keta+2
    map<int, int> yabai;
    yabai[0] =     0;
    yabai[1] =     9;
    yabai[2] =    99;
    yabai[3] =   900;
    yabai[4] =  9999;
    yabai[5] = 90000;
    if(ans%2 == 0){
    	for(int i = 1; i < M; i+2){
        ans+=yabai[ans-i];
        }
    }
    else{
    ans+=N-yabai[ans-1];
        for(int i = 2; i < K; i+2){
        ans+=yabai[ans-i];
        }
    }
    cout << ans << endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:14:5: error: expected ',' or ';' before 'map'
   14 |     map<int, int> yabai;
      |     ^~~
a.cc:15:5: error: 'yabai' was not declared in this scope
   15 |     yabai[0] =     0;
      |     ^~~~~
Language: C++

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
  string a;
  int ans=0,n;
  cin>>a;
  n=str.length(a);
  for(int i=1;n<=i;i++){
    if(i%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:9:5: error: 'str' was not declared in this scope; did you mean 'std'?
    9 |   n=str.length(a);
      |     ^~~
      |     std
Language: C++

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
  string a;
  int ans=0,n;
  cin>>a;
  n=length(a);
  for(int i=1;n<=i;i++){
    if(i%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:9:5: error: 'length' was not declared in this scope
    9 |   n=length(a);
      |     ^~~~~~
Language: C++

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
  string a;
  int ans=0;
  cin>>a;
  n=length(a);
  for(int i=1;n<=i;i++){
    if(i%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:9:3: error: 'n' was not declared in this scope
    9 |   n=length(a);
      |   ^
a.cc:9:5: error: 'length' was not declared in this scope
    9 |   n=length(a);
      |     ^~~~~~
Language: C++

#include<iostream>
#include<string>
#include<vector>
using namespase std;
int main(){
  string a;
  int ans=0;
  cin>>a;
  n=length(a);
  for(int i=1;n<=i;i++){
    if(i%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}


Compiler output:
a.cc:4:7: error: expected nested-name-specifier before 'namespase'
    4 | using namespase std;
      |       ^~~~~~~~~
a.cc: In function 'int main()':
a.cc:6:3: error: 'string' was not declared in this scope
    6 |   string a;
      |   ^~~~~~
a.cc:6:3: note: suggested alternatives:
In file included from /usr/include/c++/14/iosfwd:41,
                 from /usr/include/c++/14/ios:40,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/c++/14/bits/stringfwd.h:77:33: note:   'std::string'
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
In file included from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44:
/usr/include/c++/14/string:76:11: note:   'std::pmr::string'
   76 |     using string    = basic_string<char>;
      |           ^~~~~~
a.cc:8:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    8 |   cin>>a;
      |   ^~~
      |   std::cin
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:8:8: error: 'a' was not declared in this scope
    8 |   cin>>a;
      |        ^
a.cc:9:3: error: 'n' was not declared in this scope
    9 |   n=length(a);
      |   ^
a.cc:9:5: error: 'length' was not declared in this scope
    9 |   n=length(a);
      |     ^~~~~~
a.cc:13:3: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   13 |   cout<<ans<<endl;
      |   ^~~~
      |   std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:13:14: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   13 |   cout<<ans<<endl;
      |              ^~~~
      |              std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
Language: C++

#include<iostream>
#include<string>
#include<vector>
int main(){
  string a;
  int ans=0;
  cin>>a;
  n=length(a);
  for(int i=1;n<=i;i++){
    if(i%2==1) ans++;
  }
  cout<<ans<<endl;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:5:3: error: 'string' was not declared in this scope
    5 |   string a;
      |   ^~~~~~
a.cc:5:3: note: suggested alternatives:
In file included from /usr/include/c++/14/iosfwd:41,
                 from /usr/include/c++/14/ios:40,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/c++/14/bits/stringfwd.h:77:33: note:   'std::string'
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
In file included from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44:
/usr/include/c++/14/string:76:11: note:   'std::pmr::string'
   76 |     using string    = basic_string<char>;
      |           ^~~~~~
a.cc:7:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    7 |   cin>>a;
      |   ^~~
      |   std::cin
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:7:8: error: 'a' was not declared in this scope
    7 |   cin>>a;
      |        ^
a.cc:8:3: error: 'n' was not declared in this scope
    8 |   n=length(a);
      |   ^
a.cc:8:5: error: 'length' was not declared in this scope
    8 |   n=length(a);
      |     ^~~~~~
a.cc:12:3: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   12 |   cout<<ans<<endl;
      |   ^~~~
      |   std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:12:14: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   12 |   cout<<ans<<endl;
      |              ^~~~
      |              std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
Language: C

#include <stdio.h>
#include <string.h>
int main(void)
{
  int n,i,x,A[6];
  char s[7];
  
  scanf("%d",&n);
  
  for(i=0;i<n;i++){
    snprintf(s,7,"%d",i);
   if(strlen(s)%2==1) x++;
  printf("%d",x);
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:15:1: error: expected declaration or statement at end of input
   15 | }
      | ^
Language: C

#include <stdio.h>
#include <string.h>
int main(void)
{
  int n,i,x,A[6];
  char s[7];
  
  scanf("%d",&n);
  
  for(i=0;i<n;i){
    snprintf(s,7"%d",i)
   if(strlen(s)%2==1) x++;
  printf("%d",x);
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:17: error: expected ')' before string constant
   11 |     snprintf(s,7"%d",i)
      |             ~   ^~~~
      |                 )
main.c:11:5: error: too few arguments to function 'snprintf'
   11 |     snprintf(s,7"%d",i)
      |     ^~~~~~~~
In file included from main.c:1:
/usr/include/stdio.h:385:12: note: declared here
  385 | extern int snprintf (char *__restrict __s, size_t __maxlen,
      |            ^~~~~~~~
main.c:11:24: error: expected ';' before 'if'
   11 |     snprintf(s,7"%d",i)
      |                        ^
      |                        ;
   12 |    if(strlen(s)%2==1) x++;
      |    ~~                   
main.c:15:1: error: expected declaration or statement at end of input
   15 | }
      | ^
Language: C

#include <stdio.h>
#include <string.h>
int main(void)
{
  int n,i,x,a[6];
  char s[7];
  
  scanf("%d",&n);
  
  A[0]=n/100000;
  A[1]=(n%100000)/10000;
  A[2]=(n%100000%10000)/1000;
  A[3]=(n%100000%10000%1000)/100;
  A[4]=(n%100000%10000%1000%100)/10;
  A[5]=((((n%100000)%10000)%1000)%100)%10;
  x=0;
  for(i=0;i<6;i++)
    s[i]=A[i]+'0';
  s[6]='/0';
  for(i=1;i<=n;i++)
    if(strlen(s)%2==1) x++;
  printf("%d",x);
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:10:3: error: 'A' undeclared (first use in this function)
   10 |   A[0]=n/100000;
      |   ^
main.c:10:3: note: each undeclared identifier is reported only once for each function it appears in
main.c:19:8: warning: multi-character character constant [-Wmultichar]
   19 |   s[6]='/0';
      |        ^~~~
main.c:19:8: warning: overflow in conversion from 'int' to 'char' changes value from '12080' to '48' [-Woverflow]
Language: C

#include <stdio.h>
#include <string.h>
int main(void)
{
  int n,i,x;
  char s[5];
  
  scanf("%d",&n);
  
  x=0;
  s=(char)n;
  for(i=1;i<=n;i++)
    if(strlen(s)%2==1) x++;
  printf("%d",x);
  return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:4: error: assignment to expression with array type
   11 |   s=(char)n;
      |    ^
Language: C++

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

int main() {
    int N;
    cin >> N;
    if (N == 100000) {
        cout << 90909 << endl;
    }
    if (N >= 10000 && N < 100000) {
        cout << N - 9999 + 909 << endl;
    }
    if (N >= 1000 && N < 9999) {
        cout << 909 << endl;
    }
    if (N >= 100 && N < 1000) {
        cout << N - 99 + 9 << endl;
    }
    if (N > 10 && N < 100) {
        cout << 9 << endl;
    }
    if (N =< 10) {
        cout << N << endl;
    } 
}

Compiler output:
a.cc: In function 'int main()':
a.cc:22:12: error: expected primary-expression before '<' token
   22 |     if (N =< 10) {
      |            ^
Language: C++

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

bool f(int x){
  int keta = 0;
  while (x){
    keta++;
    x /= 10;
  }
  return keta%2 == 1;
}
int main() {
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    if (f(i)) ans++;
  }
  cout << ans << endl;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:16:15: error: 'ans' was not declared in this scope; did you mean 'abs'?
   16 |     if (f(i)) ans++;
      |               ^~~
      |               abs
a.cc:18:11: error: 'ans' was not declared in this scope; did you mean 'abs'?
   18 |   cout << ans << endl;
      |           ^~~
      |           abs
Language: C

#include<stdio.h>
#include<string.h>
int main(void){
  int l,cnt=0,i,num,even=0;
  scanf("%d",&l);
  for(i=1;i<=l;i++){
    num=i;
    even=0
    while(num>0){
      num/=10;
      even++;
    }
    if(cnt%2==0){
      i++;
      continue;
    }else{
      cnt++;
    }
  }
  return 0;
}


Compiler output:
main.c: In function 'main':
main.c:8:11: error: expected ';' before 'while'
    8 |     even=0
      |           ^
      |           ;
    9 |     while(num>0){
      |     ~~~~~
Language: C

#include<stdio.h>
int main(void){
    int n, i, s=0;
    scanf("%d",&n);
    for(i=1;i<=n;i++){
        if((i>0)&&(i<10)) s+=1;
        else if((i>100)&&(i<1000)) s+=1;
        else if((i>10000)&&(i<100000)) s+=1;
    printf("%d\n",s);
    return 0;
}

Compiler output:
main.c: In function 'main':
main.c:11:1: error: expected declaration or statement at end of input
   11 | }
      | ^
Language: C++

#include<bits/stdc++.h>
using namespace std;
int main(){
int N;
  cin>>N;
  int count=0;
 for(int i=0;i<N+1){
 str = std::to_string(i);
   int n=str.size();
   if(n%2==1){
   count++;
   }
 
 }
 cout<<count<<endl; 

}

Compiler output:
a.cc: In function 'int main()':
a.cc:7:19: error: expected ';' before ')' token
    7 |  for(int i=0;i<N+1){
      |                   ^
      |                   ;
a.cc:8:2: error: 'str' was not declared in this scope; did you mean 'std'?
    8 |  str = std::to_string(i);
      |  ^~~
      |  std