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>
#include<string>
#include<algorithm>
#include<map>
#include<set>
#include<utility>
#include<vector>
#include<cmath>
#include<cstring>
#include<cstdio>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define rp(a) while(a--)
#define pb push_back
#define mp make_pair
#define all(in) in.begin(),in.end()
const double PI=acos(-1);
const double EPS=1e-10;
using namespace std;
typedef long long ll;
typedef vector<int> vi;
int main(){
	double n;
	while(cin>>n){
		double t=n/9.8;
		double y=t*t*4.9;
		int ans=1;
		while(5*ans-5<y)ans++;
		cout<<ans<<endl;
	}
}

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

  return 0;
}

C++: #include <stdio.h>
int main() {double h;while (scanf("%lf",&h)!=EOF) printf("%d\n",(int)((((h*h*4.9/9.8)/9.8+5.0)/5.0)+0.5+1e-9)); return 0;}

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

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

C++: #include <bits/stdc++.h>

using namespace std;

int main() {

    int floor;
    double t, y, speed;

    while(cin >> speed) {

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

        for(floor = 1; (double)5 * floor - 5 < y; floor++);

        cout << floor << endl;

    }

}

C++: #include <iostream>
#define G 9.8
using namespace std;

int main()
{
  double v;
  while(cin >> v){
    int y = v * v / (2 * G);
    cout << (y + 5) / 5 + 1 << endl;
  }
}

C++: #include<iostream>
using namespace std;
int main(){
int i,n;
double v,y;
while(cin>>v){
cout<<int(v*v/98+2)<<endl;
}
return 0;
}

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

using namespace std;

int main(){
	double v,t,y,N;
	int n;
	
	while(scanf("%lf",&v)!=EOF){
		t = v/9.8;
		y = 4.9*t*t;
		N = (y+5)/5;
		n = (int)N;
		if(n==N)
		printf("%d\n",n);
		else
		printf("%d\n",n+1);
	}
}

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

int main(void){
    double v;
    double h;
    double N;
    while(cin>>v){
        h=v*v/(2*9.8);
        N=h/5+1;
        cout<<ceil(N)<<endl;
    }
    return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int main(){
double n;
while(scanf("%lf",&n)!=EOF){
n=n/9.8;
n=n*n*4.9;
int i;
for(i=1;i*5-5<n;i++);
cout<<i<<endl;
}
return 0;
}

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

int main() {
  double v;
  while (cin >> v) {
    double t = v / 9.8;
    double n = (4.9 * t * t + 5) / 5;
    cout << ceil(n) << "\n";
  }
}

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


int main()
{
	double s;
	while (cin >> s){
		for (int i = 1;; i++){
			double h = 5 * i - 5;
			double v = sqrt(2 * 9.8 * h);
			if (v >= s){
				cout << i << endl;
				break;
			}
		}
	}
	return 0;
}

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

using namespace std;

int main()
{
	double v;

	while (cin >> v)
	{
		cout << static_cast<int>((4.9 * pow(v / 9.8, 2) + 10 - 1e-7) / 5) << endl;
	}

	return 0;
}

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

int main(void){

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

        t = v / 9.8;
        y = t * t * 4.9;
        ans = y / 5 + 1;
        cout << (int)(ans+1) << endl; 
    }
    return 0;
}

C++: #include <stdio.h>

int main(void){
	double N;
	double v;
	while(scanf("%lf",&v)){
		//1/2*v^2=g*5(N-1)
		//??????????????§?????????????????¨?????????????????????
		N=v*v/(10.0*9.8)+1.0;
		printf("%d\n",(int)(N) + 1);
	}
	return 0;
}

C++: #include<cstdio>
#include<cmath>
#include<iostream>
#include<algorithm>
#define PI 3.1415926535897932384626433
using namespace std;
int main(){
    double a;
    while(cin>>a){
        a=a*a/19.6;
        cout<<(int)a/5+2<<endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i=0; i<(n); ++i)

int main(void){
    double v;
    while(cin >> v) {
        for(int n=1; ; ++n) {
            double t = sqrt((5*n-5)/4.9);
            if(9.8*t > v) {
                cout << n << endl;
                break;
            }
        }
    }
}

C++: #include <stdio.h>

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

  while( scanf("%Lf",&v)!=EOF || i<50){
    floar = (v*v/98) + 2;
    //  if((floar-(int)floar) != 0){
    //floar+=1;
    //}
    printf("%d\n", (int)floar);
    i++;
  }

  return 0;
}

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

int main(){
	int n;
	while(cin >> n){
		n = n*n/98+2;
		cout << n <<"\n";
	}
	return 0;
}

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

using namespace std;

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

C++: #include <stdio.h>
#include <math.h>
int main() {double h;while (scanf("%lf",&h)!=EOF) printf("%d\n",(int)(ceil((((h*h*4.9/9.8)/9.8+5.0)/5.0)+1e-9))); return 0;}

C++: #include <algorithm>
#include <cmath>
#include <climits>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <cassert>
#include <functional>

using namespace std;

#define LOG(...) printf(__VA_ARGS__)
//#define LOG(...)
#define FOR(i,a,b) for(int i=(int)(a);i<(int)(b);++i)
#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())
#define RSORT(c) sort((c).rbegin(),(c).rend())
#define CLR(a) memset((a), 0 ,sizeof(a))

typedef long long ll;
typedef unsigned long long ull;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vb> vvb;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int dx[] = { -1, 0, 1, 0 }; const int dy[] = { 0, 1, 0, -1 };

int main() {
	float a;
	while (cin >> a){
		cout<< ceil((a*a / 19.6f)/5.0)+1<<endl;
		
	}
}

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

const double EPS = 1.0e-6;
int main(){
	double v;
	while(cin>>v){
		double y = 4.9*v*v/9.8/9.8;
		int N = (y+5)/5 + 1;
		cout<<N<<endl;
	}
	return 0;
}

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 + 2;
        cout << N << endl;
    }
}

C++: #include <iostream>

using namespace std;

int main() {

	double v, t, y;
	int N, i, h[100000];

	for(i=0; i<100000; i++) {
		h[i]=5*i-5;
	}

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

		N=(int)((y+5)/5);
		for(i=0; i<100000; i++) {
			if(h[i]>=y) {
				N=i;
				break;
			}
		}
		cout << N << endl;
	}

	return 0;

}

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

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;
}