Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"fmt"
)

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		a, _ := strconv.ParseFloat(scanner.Text(), 64)
			t := a/9.8
			x := t*t*4.9
			fmt.Printf("%d\n", int(x))
	}
}

C++: #include <iostream>
using namespace std;

int main(){
	double v, t, y;
	int n, h[100000];
	
	for(int i=0 ; i<100000 ; i++){
		h[i] = i*5-5;
	}

	while(cin >> v){
		t = v / 9.8;
		y = t*t*4.9;
		n = (int)( (y+5.0)/5.0 );
		for(int i=0 ; i<100000 ; i++){
			if(h[i]>=y){
				n = i;
				break;
			}
		}
		cout << n << endl;
	}
	return 0;
}

C++: #include <iostream>
using namespace std;

int main(){
	double v, y, t;
	int n;
	while(cin >> v){
		t = v/9.8;
		y = 4.9*t*t;
		n = 0;
		while(5*n - 5 < y){
			n++;
		}
		cout << n << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <sstream>
#include <stdio.h>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <math.h>
#include <utility>
#include <string>
#include <ctype.h>
#include <cstring>
#include <cstdio>
#include <sstream>
#include <functional>

using namespace std;

#define FOR(i,k,n) for(int i = (k); i < (n); i++)
#define REP(i,n) FOR(i,0,n)
#define INF 114514810
#define ll long long
//#define scanf scanf_s

int main()
{
	double n;
	while (cin >> n)
	{
		FOR(i, 1, 114514)
		{
			int h = i * 5 - 5;
			double t = sqrt(h / 4.9);
			double v = 9.8*t;
			if (v > n)
			{
				cout << i << endl;
				break;
			}
		}
	}

	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;

int main(){
	double v, t;
	while(cin >> v){
		cout << (int)((4.9*(v/9.8)*(v/9.8)+5)/5+0.5)  << endl;

	}
}

C++: #include <stdio.h>
#include <math.h>
#define EPS (1e-12)

bool can(int n, double v) {
    double h = 5*n-5;
    return 9.8*sqrt(h/4.9) > v-EPS;
}

int main() {
    double v;
    while (scanf("%lf", &v) != EOF) {
        int l = 1, r = 1<<28;
        while (r-l>1) {
            const int mid = (l+r) / 2;
            if (can(mid, v)) r = mid;
            else l = mid;
        }
        printf("%d\n", r);
    }
    return 0;
}

C++: #include <cstdio>
#include <cmath>

using namespace std;

inline double sq(double x) {
  return x * x;
}

int main() {
  double v;
  while (scanf("%lf", &v) == 1)
    printf("%d\n", int(ceil(4.9 * sq(v / 9.8) / 5.0)) + 1);
  return 0;
}

C++: #include <iostream>
#include <cmath>

using namespace std;

int main() {
    double v, t;
    int y;
    while (cin >> v) {
        t = v / 9.8;
        y = ceil(4.9 * t * t);
        while (y % 5 != 0) {
            y++;
        }
        cout << y / 5 + 1 << endl;
    }

    return 0;
}

C++: #include <stdio.h>
using namespace std;
int main ()
{
    double v,t,y,n;
    while(scanf("%lf",&v)!=EOF){
        n=0;
        y=4.9*(v/9.8)*(v/9.8);
        if((int)y%5==0){
            n=y/5+1;
        }
        else n=y/5+2;
        printf("%d\n",(int)n);
    }
    return 0;
}

C++: #include <iostream>

int main(){
    double v;
    while(std::cin >> v){
            int n = 1;
            for(; v * v > 2 * 9.8 * (5 * n - 5); n++){}
            std::cout << n << std::endl;
    }
}

C++: //include
//------------------------------------------
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <queue>
#include <iterator>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

//math
//-------------------------------------------
template<class T> inline T sqr(T x) {return x*x;}

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;
typedef unsigned long long ULL;

//container util
//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())

//repetition
//------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)

//constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI  = acos(-1.0);

//clear memory
#define CLR(a) memset((a), 0 ,sizeof(a))

//debug
#define dump(x)  cerr << #x << " = " << (x) << endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

int gcd(int a, int b){
   int tmp;
   while(a%b==0){
      tmp=a%b;
      a=b;
      b=tmp;
   }
}

int lcm(int a,int b){
   return a*b/gcd(a,b);
}

bool prime_number(int n){
   if(n < 2){
      return false;
   }
   else if(n == 2){
      return true;
   }
   if(n % 2 == 0){
      return false;
   }
   for(int i=3;i<=n/i;i+=2){
      if(n % i == 0) return false;
      return true;
   }
}

int main(){
   double v,t,y;
   int n;
   while(cin>>v){
      t=v/9.8;
      y=4.9*pow(t,2);
      n=(y/5)+1;
      if(y-5*(n-1)>0) n++;
      cout << n <<endl;
   }
}

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


int main(){
  double v;
  while(cin >> v){
    double t = v/9.8;
    double y = v*v/(2*9.8);

    for(int i=0; i<2000; i++){
      if(5.0*i-5.0 >= y){
        cout << i << endl;
        break;
      }
    }
  }
}

C++: #include <iostream>
#include <cmath>
using namespace std;

int main() {
	double velocity, time, height;
	int answer;
	while (cin >> velocity) {
		time = velocity / 9.8;
		height = 4.9 * time * time;
		answer = (ceil(height) - 1) / 5 + 2;
		cout << answer << endl;
	}
	return 0;
}

C++: #include<iostream>

using namespace std;

int main(){
  double vel;
  while(cin >> vel){
	double t,y,n=1;
	t = vel/9.8;
	y = 4.9*t*t;
	while(y > 5*n-5)n++;
	cout << n << endl;
  }
  return 0;
}

C++: #include <iostream>

int main(){
	double a;
	while(std::cin>>a){
		int aa=0,n=0;
		while(aa==0){
			
			n++;
			double t=a/9.8;
			
			if(5*n-5>=4.9*t*t){
				std::cout<<n<<std::endl;
				aa=1;
				
			}
		}
		
	}
	return 0;
}

C++: #include "bits/stdc++.h"
using namespace std;

int main (void){
double a;
while(cin >> a){
double b = a / (9.8);
double c = b*b*(4.9);
double i = 1;
while(1){
if((5*i-5)>=i) break;
i++;
}
cout << i << endl;
}
return 0;
}

C++: #include <cstdio>

using namespace std;

int main()
{
	// v = 9.8t y = 4.9t^2
	
	double t,y,x;
	int n;
	
	while(scanf("%lf", &x) != EOF){
	
		t = x / 9.8;
		y = 4.9 * t * t;
		
		n = y;
		
		n /= 5;
		
		printf("%d\n", n+2);
	}
	return(0);
}

C++: #include <iostream>
#include <iomanip>
#include <list>
#include <map>
#include <algorithm>
#include <stack>
#include <string>
#include <vector>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>

using namespace std;

int main(){
	double t,v,y,n;
	while(cin >> v){
		n = 1;
		t = v / 9.8;
		y = 4.9 * t * t;

		while(1){
			if(y < 5 * n - 5){
				break;
			}
			else{
				n++;
			}
		}

		cout << n << endl;
	}

	return 0;
}