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
			ans := (x+5)/5+1
			fmt.Printf("%d\n", int(ans))
	}
}

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+=0.0000001;}
    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 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;
	}
}

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

using namespace std;

int main(void){
    double v;
    
    while (cin>>v)
    {
        double n,k;
        n = (4.9*(v/9.8)*(v/9.8)+5)/5;
        //n=(y-5)/5;
        k=n-(int)n;
        if(0.5<k){n+=1-k;}
        else {n-=k;}
        cout<<n<<endl;
    }
    return 0;
}

C++: /*****include*****/
#include <iostream>
#include <fstream>
#include <string>

/*****デバッグ定義*****/
//#define DEBUG
/*****マクロ定義*****/

/*****名前空間*****/
using namespace std;

/*****グローバル変数置き場*****/

/*****その他関数置き場*****/

/*****main関数*****/
int main(){
	/*****ファイルオープン*****/
#ifdef DEBUG
	ofstream fout("output.txt");
	ifstream fin("input.txt");
	if(!fout || !fin){
		cout << "Can't open the file.\n";
		return;
	}
#endif
	/*****変数置き場*****/
	double b_v;
	double v_sq;
	long int n;
	/*****処理部*****/
	while(1){
		cin >> b_v;
		if(b_v == 0)	break;
		n=0;
		v_sq = 0;
		while(v_sq < b_v*b_v){
			n++;
			v_sq = 19.6 * (5*(double)n - 5);
		}
		printf("%d\n",n);
	}
	/*****処理終了後*****/
#ifdef DEBUG
	fout.close();
	fin.close();
#endif
	return 0;
}

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

int main(){
    double v;
    int N;
    while(scanf("%lf",&v)!=EOF){
        N = (int)ceil((v*v)/98.0 + 1);
        printf("%d\n",N);
    }
}

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

int main() {
  double v;
  while (~scanf("%lf", &v)) {
    double n = (4.9 * (v / 9.8) * (v / 9.8) + 5) / 5;
    printf("%d\n", (int)ceil(n));
  }
}

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

int main() {
  double v;
  while(cin >> v) {
    cout << (long long)ceil(v*v/98.0+1) << endl;
  }
  return 0;
}

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

double v;
const double g = 9.8;
const double c_y = 4.9;
const int c_n = 5;
const double err = 0.0001;

double t(double v)
{
	return v / g;
}

double y(double t)
{
	return c_y * t * t;
}

int n(double y)
{
	double r = (y + c_n) / c_n;
	int r2 = (int)r;
	//if (r - r2 < err && r - r2 > -err)
	//	return r2;
	//else
		return r2 + 1;
}

int main()
{
	while (cin >> v)
	{
		cout << n(y(t(v))) << endl;
	}
	return 0;
}

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

int main(){
	double v, y;cin >> v;
	y = 4.9 * pow(v / 9.8, 2);
	cout << (int)y/5 + 2 << endl;
	return 0; 
}
//25.4

C++: #include<bits/stdc++.h>
using namespace std;
 
#define REP(i,s,n) for(int i=s;i<n;++i)
#define rep(i,n) REP(i,0,n)
#define SORT(c) sort((c).begin(),(c).end())
#define IINF INT_MAX
#define LLINF LLONG_MAX
 
typedef long long ll;
typedef pair<int, int> ii;

#define EPS 1e-8

int main(){

	vector<double> hold;
	double v  = 0;
	int i = 0;
	while(v < 300.0){
		int y = i * 5;
		double t = sqrt(y / 4.9);
		double tmp = 9.8 * t;
		hold.push_back(tmp);
		i++;
		v = tmp;
	}
	
	while(cin >> v){
		rep(i, hold.size()){
			if(v < hold[i]){
				cout << i + 1 << endl;
				break;
			}
		}
		
	}
	return 0;
}

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

using namespace std;

#define EPS (1e-10)
#define EQ(a,b) (abs((a) - (b)) < EPS)

int main(){

	double v;

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

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

int main(){
	double mv;

	while (cin >> mv)
		cout << (int)ceil((mv*mv / (9.8 * 2)) / 5.0 + 1.0) << endl;

	return 0;
}

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

using namespace std;

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

		n = ((y+5)/5)+1;

		cout << n << endl;
	}
}

C++: print(".....END.....")

C++: #include <iostream>
#include <cmath>
using namespace std;
int main(){
	double mv;
	while(cin>>mv){
		double t = mv/9.8;
		double y = t*t*4.9;
		cout << (int)ceil(y/5.0)+1 << "\n";
	}
	return 0;
}

C++: #include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cctype>
#include<cmath>
#include<iostream>
#include<algorithm>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<bitset>
#include<utility>
#include<string>

using namespace std;

main(){
  double t,v,y,n;
  int i,j,l;
  while(cin >> v){
    t=v/9.8;
    y=4.9*t*t;
    n=ceil((y+5)/5);
    printf("%.0f\n",n);
  }
}

C++: #include<iostream>
using namespace std;
int main()
{
long double v,n;
int N;
while(cin>>v)
{
n=0;
N=0;
n=4.9*(v/9.8)*(v/9.8)/5+1;
N=n*10;	
if(N%10==0)
{
	cout<<N/10<<endl;
}
else if(N%10!=0)
{
	cout<<N/10+1<<endl;
}
}
return 0;
}

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

int main()
{
    double v,y,n,t;
    while(scanf("%lf",&v)==1)
    {
        

        t=v/9.8;
        y=4.9*t*t;
        n=(y+5)/5;

        int nt=int(n);
        if(n-nt>=0.5)nt+=1;
        cout<<nt<<endl;
    }
    return 0;

}

C++: #include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<vector>
#include<string>
#include<sstream>
#include<cmath>
using namespace std;

int main(){

  double v;
  while( cin >> v ){
    double t = v / 9.8;
    double y = 4.9 * t * t;
    // cout << y << endl;
    int n = (y + 5 + 0.0000001) / 5;
    n++;
    cout << n << endl;
  }

  return 0;
}

C++: #include<iostream>
using namespace std;
int N;
double v,t,y;
int main(){
  while(cin>>v){
    t=v/9.8;
    y=4.9*t*t;
    N=2;
    while((5*N-5)<y)N++;
    cout<<N<<endl;
  }
  return 0;
}

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

int main(void){
    const double g=9.8;
    double v;
    while(std::cin>>v){
        int n=1;
        while(1){
            if(v*v<=2*g*5*(n-1)){
                std::cout<<n<<std::endl;
                  break;
            }
            n++;
        }
    }
    return 0;
}

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

int main(){
	double mv;

	while (cin >> mv)
		cout << ceil((mv*mv / (9.8f * 2)) / 5 + 1) << 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 (ans - (int)ans < 0.00000000001) {
            printf("%d\n", (int)ans + 1);
        } else {
            printf("%d\n", (int)ans + 2);
        }

    }

    return 0;
}

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

int main()
{
	double _t, t, y, N;
	while (cin >> _t){
		t = _t / 9.8;
		y = 4.9 * t * t;
		N = (y + 5) / 5;

		cout << static_cast<int>(N+1) << endl;
	}
	return 0;
}

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

int main(){
  double v;
  double h;
  int ans;
  double min;
  while(cin>>min){
    v=0;
    h=0;
    ans=1;
    for(;v<min;ans++){
      h=5*ans-5;
      v=9.8*sqrt(h/4.9);
    }
    cout<<ans-1<<"\n";
  }
  return 0;
}

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

double v;

void solve() {
    double y = v * v / 19.6;
    cout << floor(y / 5 + 2) << endl;
}

int main() {
    while (cin >> v) {
        solve();
    }
    return 0;
}