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 <vector>
#include <cmath>
#include <iomanip>
#include <string>
#include <queue>
#include <algorithm>
#include <cctype>
#define shosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const double pi=acos(-1);

double n;

int main(){
	while(cin>>n){
		int ans;
		for(int i=2;;i++){
			ans=i;
			if(n<=9.8*sqrt((double)(5*i-5)/4.9)) break;
		}
		cout<<ans<<endl;
	}
}

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

using namespace std;

int main()
{
    double input;
    double t;
    int n;

    while (cin >> input) {
        t = input / 9.8;
        n = ceil(0.1 / 9.8 * input * input + 1.0);

        cout << n << endl;
    }

    return 0;
}

C++: #include<iostream>
#include<iomanip>
#include<vector>
#include<queue>
#include<list>
#include<stack>
#include<algorithm>
#include<cmath>
#include<memory>

using namespace std;

int main()
{
  double v;

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

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

using namespace std;

double getT(double v){return v/9.8;}
double getY(double t){return 4.9*t*t;}

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

	while(cin>>v){
		int N=0;
		t=getT(v);

		y=getY(t);

		while(1){
			if(5*N-5>y)
				break;
			N++;
		}

		cout<<N<<endl;
	}
	return 0;
}

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

#define REP(i,n) for(int (i)=0; (i)<(n); (i)++)
#define FOR(i,a,b) for(int (i)=(a); (i)<(b); (i)++)
#define PUSH(n,v) for(int i=0; i<(n); i++) {int j; cin >> j; v.push_back(j);}
#define ALL(v) v.begin(), v.end()

int getFloorNum(double h) {
    return ceil(h / 5.0) + 1;
}

int main() {
    double v;
    while(cin >> v) {
        double h = v*v/19.6;
        cout << getFloorNum(h) << endl;
    }
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<cctype>
#include<cstring>
#include<cstdlib>
#include<vector>
#include<string>
#include<cmath>
using namespace std;
#define REP(i, j) for(int i = 0; i < j; i++)
#define FOR(i, j, k) for(int i = j; i < k; i++)
const double EPS = 1e-8;
const int INF = 1e9;

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

C++: #include <stdio.h>
#include <float.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 > LDBL_EPSILON)&&((int)floar > 0)){
      floar++;
    }
    printf("%d\n", (int)floar);
    i++;
  }

  return 0;
}

C++: main(){float v;for(;~scanf("%f",&v);printf("%.f\n",v*v/98+2));}

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

using namespace std;

int main()
{
	int i = 0;
	double min_v = 0, y, t, height;

	while ( cin >> min_v )
	{
		t = min_v / 9.8;
		y = 4.9 * t * t;
		height = ( y + 5 ) / 5;
		height = ceil( height );
		cout << ( int )height << 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>
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++: //Physical Experiments

#include<cstdio>
#include<cmath>
using namespace std;

int main(void){
    double v;
    int n;
    
    while(scanf("%lf", &v) != EOF){
        //??°?????????????¨??????????
        n = (int)(v*v / 98.0 + 1.0) + 1;
    
        printf("%d\n", n);
    }
    
    return 0; 
}

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

using namespace std;

const double g=9.8;
int Height(double v);

int main(){
	double v;	
	
	while( cin>>v ){
		cout<<Height(v)<<endl;
	}
	return 0;
}

int Height(double v){
	int floor;
	for( floor=0;sqrt(2*g*floor*5)<v;floor++ );
	return floor+1;
}

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

using namespace std;

int main()
{
//	cut here before submit 
//	freopen("testcase.dat", "r", stdin);
	double vb;		

	while (cin >> vb ){
		int res = 0;

		for (int n = 1;; ++n ){
			int h = 5*n - 5;
			double tt = (double)h/4.9;
			double t = sqrt(tt );
			double v = 9.8*t;
			if (v < vb){
				continue;
			}else{
				res = n;
				break;
			} // end if
		} // end for
		cout << res << endl;
	} // end for

	return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <utility>
#include <stack>
#include <functional>
#include <queue>
#include <cmath>

#define rep(i,j,k) for(int i=j;i<k;i++)
#define drep(n,m) for(int i=0;i<n;i++)for(int j=0;j<m;j++)
#define fi first
#define se second
#define vi vector<int>
#define INF 1000000000
#define MOD 1000000009
#define pb push_back
#define mp make_pair
typedef long long ll;
int dx[4]={0,1,0,-1},dy[4]={1,0,-1,0};

using namespace std;

ll gcd(ll a,ll b){
    if(a<b){
        int t=a;a=b;b=t;
    }
    int c=a%b;
    while(c!=0){
        a=b;
        b=c;
        c=a%b;
    }
    return b;
}

ll lcm(ll a,ll b){
    return a*b/gcd(a,b);
}

bool isPrime(int x){
    if(x==1)return false;
    if(x==2)return true;
    if(x%2==0)return false;
    for(int i=3;i<=sqrt(x);i+=2){
        if(x%i==0)return false;
    }
    return true;
}

int main() {
    double v;
    while(cin>>v){
        double t;
        t=v/9.8;
        double y=4.9*t*t;
        y+=5.0;
        cout<<(int)((y+4)/5)<<endl;
    }
    
  
    return 0;
}

C++: #include <cmath>
#include <iostream>
using namespace std;
int main() {
  double a;
  while (cin >> a) {
    cout << (ceil(4.9 * (a / 9.8) * (a / 9.8) / 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);
		cout << (y + 4) / 5 + 1 << endl;
	}
	
	return 0;
}

C++: #include<cstdio>

int main(){
  double target;
  while(scanf("%lf",&target)>0){
    double y = 4.9*target*target/(9.8*9.8);
    for(int n=1;;n++){
      if(5*n-5 >= y){
	printf("%d\n",n);
	break;
      }
    }
  }
}

C++: #include <stdio.h>
#include <float.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 > LDBL_EPSILON)&&((int)floar >= 1)){
      floar++;
    }
    printf("%d\n", (int)floar);
    i++;
  }

  return 0;
}

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

int main(){
	double a;
	
	while(scanf("%lf",&a) != EOF){
		a = (a*a+98)/98;
		a = ceil(a);
		printf("%d\n",(int)a);
	}
	
	return 0;
}