Go: package main

import (
        "fmt"
        "math"
)

func main() {
        var v, t, h float64
        for {
                _, err := fmt.Scanf("%f", &v)
                if err != nil {
                        break
                }
                t = v / 9.8
                h = 4.9 * t * t
                n := math.Floor(h/5+1.0) + 1.0
                fmt.Printf("%d\n", int(n))
        }
}

C++: #include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <cassert>
#include <iostream>
#include <cctype>
#include <sstream>
#include <string>
#include <list>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <utility>
#include <numeric>
#include <algorithm>
#include <bitset>
#include <complex>
#include <fstream>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vint;
typedef pair<int, int> pint;
#define rep(i, n) REP(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define MSG(a) cout << #a << " " << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
template<class T> T RoundOff(T a){ return int(a+.5-(a<0)); }
template<class T, class C> void chmax(T& a, C b){ if(a < b) a = b; }
template<class T, class C> void chmin(T& a, C b){ if(b < a) a = b; }
template<class T, class C> pair<T, C> mp(T a, C b){ return make_pair(a, b); }

int main()
{
	double v;
	while(cin >> v)
		cout << ceil((4.9 * pow(v / 9.8, 2.0) + 5) / 5) << endl;	
}

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

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

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

int main(){
	float v, h;
	int n, a;
	while (true){
		cin >> v;
		if (cin.eof()) { break; }
		h = v * v / 19.6;
		for (n = 0;;n++){
			a = 5 * n - 5;
			if (a >= h) { break; }
		}
		cout << n << endl;
	}
	return 0;
}

C++: #include <cstdio>
int main()
{
    double v,h;
    double i=1;
    while(~scanf("%lf",&v))
    {
        h=v*v/(9.8*2);
        while(1)
        {
            if((i-1)*5>=h)
            break;
            i+=1;
        }
        //int j=(int)i;
        printf("%.0lf\n",i);
    }
    return 0;
}

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

using namespace std;

int main()
{
    double v;

    while (scanf("%lf", &v) != EOF) {
        double ans = (v*v/98);
        if (v*v <= 49.0000000) {
            puts("1");
        } else if (ans - (int)ans < 0.0000001) {
            printf("%d\n", (int)ans + 1);
        } else {
            printf("%d\n", (int)ans + 2);
        }

    }

    return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>
#include <sstream>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <numeric>
#include <cmath>
#include <climits>
#include <limits>
#include <cfloat>
#include <fstream>
using namespace std;

int main()
{ 
	double v;
	double y,t;
	int N;
        while(1){
		cin>>v;
 		if(cin.eof()) return 0;
		t=v/9.8;
		y=4.9*t*t;
                N=1+(int)y/5.0;
		if((double)5.0*(N-1)==N) cout<<N<<endl;
		else cout<<(N+1)<<endl;
	}
}

C++: #include<iostream>
using namespace std;
int main(void){
    double v,t,y;
    int N;
    while(cin >> v){
        t=v/9.8;
        y=4.9*t*t;
        N=y/5 + 5;
        cout << N-3 << endl;
    }
}

C++: #include<iostream>

int Gauss2(double x)
{
	int p=x;

	if(x==(double)p || x>0)
	{
		return p;
	}
	else
	{
		return p-1;
	}

}

int main()
{
	const double g = 9.8, HiPerStair = 5.0;

	double v;

	while(std::cin >> v)
	{
		std::cout << Gauss2(v*v/g/HiPerStair/2.0+1.0)+1 << '\n';
		//vが崩壊速度なので v^2 < 2*9.8*y　で壊れる nは階数として　y=HiPerStair*(n-1)　ｎを直接求める式
	}
}

C++: #include <stdio.h>

main()
{
  long double v,floar;
  int    i=0;

  while( scanf("%Lf",&v)!=EOF || i<50){
    floar = (v*v/98) + 1;
    if((floar-(int)floar) != 0){
      floar+=1;
    }
    printf("%d\n", (int)floar);
    i++;
  }

  return 0;
}

C++: #include<iostream>
using namespace std;
int main()
{
long double v,n;
int N;
while(cin>>v)
{
n=(4.9*((v/9.8)*(v/9.8)))/5+1;
N=n*10000;	
if(N%10000==0)
{
	cout<<N/10000<<endl;
}
else if(N%10000!=0)
{
	cout<<N/10000+1<<endl;
}
}
return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
double v;
int ans;
const double eps=1e-9;
int main()
{
    while(scanf("%lf",&v)!=EOF)
    {
        ans=ceil(v*v/19.8*0.2)+1;
        cout<<ans<<endl;
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <cmath>

#define rep(x,to) for(int x=0;x<to;x++)
#define rep2(x,from,to) for(x=from;x<to;x++)

using namespace std;


int main(void){

double v,wn;
int n;

	while(cin >> v ){
		double h = 4.9 * (v / 9.8) * (v / 9.8);
		n = ceil(( h + 5 ) / 5);
//		n = (int)wn;
//		n = n + (wn==n? 0: 1);
		cout << n << endl;
	}
	
	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <cmath>
#include <algorithm>
#include <cstdlib>
#include <ctime>
#include <cstdio>
#include <functional>
#include <set>
#include <sstream>
#include <map>

using namespace std;

const double eps=1e-10;

int main()
{
	double v;
	while(cin>>v){
		unsigned long long l=1,r=1e16,h;

		while(l+1!=r){

//			cout<<l<<" "<<r<<endl;

			h=(l+r)/2;
			double vv=2.0*9.8*(5*h-5);

			if(v*v>vv) l=h;
			else r=h;
		}
		if( abs(v*v-2.0*9.8*(5*l-5))<eps ) cout<<l<<endl;
		else cout<<r<<endl;

	}

	return 0;
}

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

using namespace std;

int main()
{
    double v;

    while (scanf("%lf", &v) != EOF) {
        double ans = (v*v/98);
        if (v*v <= 49.0000000) {
            puts("1");
        } else if (ans - (int)ans < 0.000001) {
            printf("%d\n", (int)ans + 1);
        } else {
            printf("%d\n", (int)ans + 2);
        }

    }

    return 0;
}

C++: aaaaaaaa

C++: #define _USE_MATH_DEFINES
#include <iostream>
#include <queue>
#include <vector>
#include <math.h>
#include <algorithm>
#include <iomanip>
#include <string>
#include <stack>
#include <cctype>
#include <cstdlib>
using namespace std;

#define INF (1 << 20)
#define EPS (1e-10)
#define EQ(a,b) (fabs((a)-(b)) < EPS)

int main(){
	double v;
	while (cin >> v) {
		int n = 0;
		while (n - v * v / 98 + 1.0 < EPS) ++n;
		cout << n << endl;
	}
	return 0;
}

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

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

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

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

C++: #include <iostream>
#include <cmath>
#define eps 10e-9
using namespace std;

int main()
{
	double in;
	while(cin>>in)
	{
		double t=in/9.8;
		cout<<ceil((4.9*t*t+5)/5)<<endl;
	}
	return 0;
}

C++: #include <iostream>

using namespace std;

int main(void){

  double v;
  while( cin >> v ){

    double t = v / 9.8;
    double y = 4.9*t*t;

    for( int N = 1 ; N <= 1000 ; N++ ){
      if( 5 * N - 5 >= y ){
	cout << N << endl;
	break;
      }
    }

  }
  return 0;
}

C++: #include <stdio.h>

int main(){
  int n,N;
  double x,y,v,t;

  while(scanf("%lf",&v)!=EOF){

    t=v/9.8;

    y=4.9*t*t;
    
    for(n=0;y>=5*n-5;n++);

    N=n;
    
    printf("%d\n",N);
  }
  
  return 0;
  
}