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>
#include <cmath>
using namespace std;

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

C++: #include <iostream>

using namespace std;

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

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

int main()
{
	double v;
	while(cin>>v)
	{
		double h=v*v/(2*9.8);
		int n=ceil((double)(h+5)/5);
		if(h==0)
		  cout<<"0"<<endl;
		else
		  cout<<n<<endl;
	} 
 return 0;
}

C++: #include<stdio.h>
#include<math.h>
#include<algorithm>
#include<cstring>
using namespace std;
//long long int arr[1000000];
int main()
{
    int a;
    double v,b;
   while(scanf("%lf",&v)==1)
   {
       v/=9.8;
       v=((v*v)*4.90)/5+1;
       a=v;
       b=v-a;
       if(b<0)
       printf("%d\n",a);
       else
       printf("%d\n",a+1);
   }
   return 0;
}

C++: #include<cstdio>
using namespace std;
int main()
{
    int n,i,res;
    double t,v,h;
    while(scanf("%lf", &v)==1)
    {
        t=(v/9.8);
        h=4.9*t*t;
        for(n=1;;n++)
        {
            res=5*n-5;
            if(res>h)
                break;
        }
        printf("%d\n",n);
    }
    return 0;
}

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

int main()
{
    for (double v; cin >> v;)
        cout << ceil((4.9 * v * v / 9.8 / 9.8 + 5) / 5) << endl;

    return 0;
}

C++: //#define _USE_MATH_DEFINES
#include <cmath>
#include <iostream>
//#include <stdio.h>
//#include <stdlib.h>
//#include <iomanip>
#include <vector>
//#include <string>
//#include <algorithm>
//#include <functional>
//#include <time.h>
//#include <sstream>
//#include <queue>

using namespace std;


int main(){

	const int H = 5;
	double v, t, y;
	long long ans;

	while (cin >> v){
		t = v / 9.8;
		y = 4.9 * t * t;
		ans = (long long)(ceil(y / H)+1);
		cout << ans << endl;
	}


	return 0;
}

C++: #include<iostream>
using namespace std;
int main(){
  double a,b,c;
  while(cin>>a){
    b=0;int s=0; 
    while(1){if(9.8*b>=a)break;b+=0.000001;}
    while(1){
      if(4.9*b*b<=s)break;
      s+=5;
    }cout<<s/5+1<<endl;
  }
}

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

int main(){
	double mv;
	while (cin >> mv)
		cout << ceil((mv*mv / (9.8f * 2)) / 5 + 1) << endl;
}

C++: #include <iostream>
#include <iomanip>
#include <math.h>
#include <utility>
#include <vector>
#include <cstdlib>
#include <algorithm>
#include <climits>
using namespace std;

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

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

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

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

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

C++: #include<bits/stdc++.h>
using namespace std;
int main(void){
	double v,t;
	double y;
	int ans;
	while(1){
		cin>>v;
		if(cin.eof()==1)	break;
		t=v/9.8;
		y=4.9*pow(t,2);
		y+=5;
		if(fmod(y,5.0)!=0){
			y/=5;
			y++;
		}
		else	y/=5;
		ans=y;
		cout<<ans<<endl;
	}
	return 0;
}

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

using namespace std;

int main(){
	double  v;

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

		cout << (int)((49*2*v*v)/(98*98) + 1 + 0.9) << endl;
	}
	return 0;
}

C++: #include <cmath>
#include <iostream>
#define	GA	9.8

int main() {
	double v;
	double y;
	int n;
	while (std::cin >> v) {
		y = v * v / (2. * GA);
		n = ceil((y + 5.) / 5.);
		std::cout << n << '\n';
	}
	return 0;
}

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

C++: #include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
int main(){
  double v,y,t;
  int n;
  while(cin >> v){
    t = (v/9.8);
    y = 4.9 * (t*t);
    for(int i=1;i<=10000;i++){
      n = 5 * i - 5;
      if((int)y<n){
	cout << i << endl;
	break;
      }
    }
  }
}

C++: #include <iostream>
using namespace std;
int main() {
    double v;
    while (cin >> v) {
        cout << (int)(v * v * 1 / 98 + 1.9999999999999999) << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <cstring>
#include <climits>
#include <cmath>
#include <cfloat>

using namespace std;

double vn, yn, out, tn;

int main()
{
	
	while( cin >> vn, !cin.eof())
	{
		tn = vn/9.8;
		
		yn = tn*tn*4.9;
		
		for( int i = 1; i < INT_MAX; i++)
		{
			int f = 0;
			double flr = (double)(i-1)*5.0;
			
			if( flr >= yn )
			{
				cout << i << endl;
				f = 1;
				break;
			}
			
			if(f)
				break;
		}
		
	}
	
	return 0;
}

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

int main(void){

    int ans;
    double N;
    double v,t;
    
    while(cin >> v){

        t = v / 9.8;

        N = (4.9 * t * t + 5) / 5;

        if(N -(int)N > 0.50){
            ans = (int)(N + 1);
        }else{
            ans = (int)N;
        }
        cout << ans << endl;
    }


    return 0;
}

C++: #include <iostream>

using namespace std;

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

    for (int N = 1;; ++N)
      if ((5 * N - 5) > y) {
	cout << N << endl;
	break;
      }
  }
  
  return 0;
}

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

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

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

int cont(float y)
{
    int cont = 1;
    while(y>0){	
	y -= 5;
	cont++;
    }
    return cont;
}

int main()
{
    float y, nv;
    while(cin >> nv)
    {
	y = (nv * nv) / 19.6;
	
	cout << cont(y) << endl;
    }
}

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

int main()
{
  double v0;
  while (scanf("%lf ", &v0) == 1) {
    cout << (int)((v0 * v0)/ (5.0 * 4.0 * 4.9)) + 2 << endl;
  }
}

C++: #include <iostream>

using namespace std;

int main()
{
	double v, y, t;
	int floor;

	while (cin >> v)
	{
		if(cin.eof())    break;

		t = v / 9.8;
		y = 4.9 * t * t;
	
		floor = int(y/5 + 0.9999999999)+1;

		cout << floor << endl;
	}

	return 0;
}

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

int main()
{
    double v;

    while(cin>>v)
    {
        double sum= (v*v/19.6+5)/5;
        int n=0;
        while(sum>n)
            n++;
        cout<<n<<endl;
    }
    return 0;
}

C++: /*AOJ 0024*/

#include<iostream>
using namespace std;

int f(double v){
	double t = v/9.8;

	double y = 4.9 * t * t;

	int ans = (y / 5);

	if(y == (int)y){
		return ans+1;
	}
	else{
		return ans+2;
	}
}


int main(){

	double v;

	while(cin>>v){
		cout<<f(v)<<endl;
	}

	return 0;
}