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>
int main(){
    double s;
    while(~scanf("%lf",&s)){
        double y=(4.9*(s/9.8)*(s/9.8))+5;
        if(y==(int)(y/5)*5) printf("%d\n",(int)y/5);
        else printf("%d\n",(int)y/5+1);
    }
}

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

int main()
{
	double minv, v=0.0, y=0.0;
	double t, high = 0.0;
	int f=1;

	while (cin >> minv)
	{
		high = 0;
		t = minv / 9.8;
		y = 4.9 * t * t;
		for (f = 0; high <= y; f++)
		{
			high = f * 5 - 5;
		}
		if (high != y) f--;
		cout << f << endl;
	}
	return 0;
}

C++: #include<iostream>

using namespace std;



main(){
  double minv;
  while(cin >>minv){
    int i;
    double t = minv/9.8;
    double y;
    y = 4.9*t*t;
    double tall;
    for(i=1;y>=tall ; i++){
      tall = 5*i-5;
    }

    cout << --i << endl;


  }





  return 0;
}

C++: #include <iostream>

using namespace std;

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

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

// ?????¬???????????¬??????
#pragma region MACRO
#define P(x) cout << (x) << endl
#define p(x) cout << (x)
#define PED cout << "\n"
#define rep(i,n) for(int i=0; i<(int)n; ++i)
#define REP(i,x,n) for(int i=x; i<(int)n; ++i)
#define repi(i,n) for(int i=0; i<=(int)n; ++i)
#define REPI(i,x,n) for(int i=x; i<=(int)n; ++i)
#define ILP while(true)
#define FOR(i,c) for(__typeof((c).begin())!=(c).begin(); i!=(c).end(); ++i)
#define ALL(c) (c).begin(), (c).end()
#define mp make_pair
#pragma endregion

// ???
#pragma region TYPE_DEF
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<string, string> pss;
typedef pair<string, int> psi;
typedef pair<int, string> pis;
typedef vector<int> vi;
typedef vector<double> vd;
typedef vector<long double> vld;
typedef vector<long> vl;
typedef vector<long long> vll;
typedef vector<string> vs;
#pragma endregion

// Effective std
#pragma region ESTD
template<typename C, typename T> int count(C& c, T t) { return count(ALL(c), t); }
template<typename C, typename F> int count_if(C& c, F f) { return count_if(ALL(c), f); }
template<typename C, typename T> void erase(C& c, T t) { remove(ALL(c), t), c.end(); }
template<typename C> void remove(vector<C>& c, unsigned int index) { c.erase(c.begin()+index); }
template<typename C, typename T, typename U> void replace(C& c, T t, U u) { replace(ALL(c), t, u); }
template<typename C, typename F, typename U> void replace_if(C& c, F f, U u) { (ALL(c), f, u); }
template<typename C> void reverse(C& c) { reverse(ALL(c)); }
template<typename C> void sort(C& c) { sort(ALL(c)); }
template<typename C, typename Pred> void sort(C& c, Pred p) { sort(ALL(c), p); }
#pragma endregion

// ?????°
#pragma region CONST_VAL
constexpr int PI = (2*acos(0.0));
constexpr int EPS = (1e-9);
constexpr int MOD = (int)(1e9+7);
constexpr int INF = 100000000;
#pragma endregion


int main()
{
    double v;
    while(cin >> v) {
        double t = v / 9.8;
        double y = t * t * 4.9;
        int n = 1;
        while(n * 5 - 5 < y) n++;
        P(n);
    }
    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 (ans - (int)ans < 0.000000001) {
            printf("%d\n", (int)ans + 1);
        } else {
            printf("%d\n", (int)ans + 2);
        }

    }

    return 0;
}

C++: #include<cstdio>
#include<cstring>
#include<algorithm>
#include<functional>
using namespace std;
int main(void)
{
	int i,j,y,cnt;
	double n,x,raka;
	while(scanf("%lf",&n)!=EOF) {
		cnt=1;
		x=n/9.8;
		raka=4.9*(x*x);
		i=1;
		while(1) {
			if(5*i-5<raka) cnt++;
			else break;
			i++;
		}
	}
	printf("%d\n",cnt);
	return 0;
}

C++: #include<iostream>
using namespace std;
int main(){
  double v,t,y;
  int sy;
  while(cin>>v){
    t=v/9.8;
    y=4.9*t*t;
    sy=0;
    while(1){
      if((5*sy-5)>y){
	break;
      }
      sy++;
    }
    cout<<sy<<endl;
  }
  return 0;
}

C++: #include <iostream>

using namespace std;

void storey(double);

int main() {

	double min;

	while(cin>>min) {
		storey(min);
	}

	return 0;

}

void storey(double min) {

	double t, y, N;

	t=min/9.8;
	y=4.9*t*t;

	N=y/5+1;
	N+=0.9;
	N=(int)N;

	cout << N << endl;

}

C++: #include<iostream>
#include<math.h>

using namespace std;

int main(void)
{
	double input;
	while(cin>>input)
	{
		for(int i=0;;i++)
		{
			double t=sqrt((5*i-5)/4.9);
			if(9.8*t>input)
			{
				cout<<i<<endl;
				break;
			}
		}
	}
}

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

using namespace std;

int main() {
	double v;
	while (scanf("%lf", &v) != EOF) {
		printf ("%lld\n", (long long)((v * v / 19.6 + 5) / 5.0 + 0.5));
	}
	return 0;
}

C++: #include "stdafx.h"
#include <iostream>
#include <string>
#include <stack>
#include <math.h>
#include <algorithm>
#include <cstdlib>
#include <ctime>
#include <vector>

using namespace std;





int main()
{
	double v;
	double h;
	int n = 1;
	while (cin >> v) {
		h = 4.9*(v / 9.8)*(v / 9.8);
		while (h > 5 * (n - 1)) {
			n++;
		}
		cout << n << endl;
	}


	return 0;
}

C++: #include <iostream>
#define rep(i, a, n) for(int i = a; i < n; i++)
using namespace std;

int main(){
    double v;
    while(cin >> v){
        double t = v / 9.8;
        double y = t * t * 4.9;
        int ans = 0;
        rep(i, 0, 60){
            int h = 5 * (i - 1);
            if(h > y){
                ans = i;
                break;
            }
        }
        cout << ans << endl;
    }
}