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 <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
using namespace std;
static const double EPS = 1e-5;
typedef long long ll;
#define FOR(i,n) for(i=0;i<n;i++)
#define rep(i,n) for(int i=0;i<n;i++)

int main(){
	double s;
	for(;cin>>s;){
		double t=s/9.8;
		double y=4.9*t*t;
		cout<<(int)(y/5+1.99999)<<endl;
	}
	return 0;
}

C++: #include<bits/stdc++.h>
#include<vector>
#include<list>
#include<stack>
#include<queue>
#include<algorithm>
using namespace std;

int main(){
    int mod=1000000007;
    int n;
    int ans;
    double v;
    while (scanf("%lf",&v)!=EOF) {
        double t=v/9.8;
        double y=t*t*4.9;
        //int n=int(floor((y+5.0)/5.0));
        int tmp;
        for (int j=0;;j++) {
            if ((j*5-5)*1.0>=y) {
                tmp=j;
                break;
            }
        }
        printf("%d\n",tmp);
    }
    return 0;
}

C++: #include <cstdio>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <string.h>
#include <bitset>
#include <queue>
#include <map>
#include <string>
#include <stack>
#include <utility>
#include <queue>
#include <cmath>
#define mp make_pair
#define pii pair<long long int,long long int> 
#define ff first
#define pb push_back
#define ss second
#define ll long long 
#define ull unsigned long long
#define vi vector<long long int>
#define vii vector<pii>
#define vvi vector <vi>
#define rep(x,a,b,c) for(int x=a;x<=b;x+=c)
#define repp(x,a,b) rep(x,a,b,1)
#define rev(x,a,b,c) for(int x=a;x>=b;x-=c)
#define revv(x,a,b) rev(x,a,b,1)
#define OO (int)2e9
#define INF (ll)1e18
 
using namespace std;

double h;

int main()
{
	while(scanf("%lf",&h)!=EOF)
	{
		printf("%d\n",(int)ceil(h*h/(double)98)+1);
	}
	return 0;
}

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

int main(){
	double n;
	int k = 0;
	int out[1000];
	while(cin >> n){
		double v, t;
		for(int i = 1; i < 1000; i++){	
			t = sqrt((5*i-5)/4.9);
			v = 9.8*t;
			if(v >= n){
				out[k] = i;
				break;
			}
		}
		k++;
	}
	for(int i = 0; i < k; i++){
		cout << out[i] << endl;
	}
}

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

int main() {
    double v;
    while (cin >> v) {
        int N = 0;
        for ( ; ; ++N) {
            int y = 5 * N - 5;
            if (v * v * 10 <= 196 * y) break;
        }
        cout << N << endl;
    }
    return 0;
}

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

#include<vector>

#define INF 999999
using namespace std;
int main(){
    double high,Y,i;
    while(~scanf("%lf",&high)){
        int F=1;
        for(i=1.0;i<100;i+=0.1){
            if(9.8*i>=high)break;
        }
        Y=4.9*(i*i);
        for(;;){
            if(Y<=0)break;
            Y-=5;
            F++;
        }
        cout<<F<<endl;
    }
    return 0;
}

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

C++: #include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;
int main() {
	double d;
	double EPS = 1e-5;
	while(scanf("%lf", &d) == EOF) {
		cout << ceil((4.9 * pow(d / 9.8, 2.0) + 5.0 + EPS) / 5.0) << 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) + 4;
		cout << y / 5 + 1 << endl;
	}
	
	return 0;
}

C++: #ifndef _GLIBCXX_NO_ASSERT
#include <cassert>
#endif
#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

#ifdef __GXX_EXPERIMENTAL_CXX0X__
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
#endif

#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>

#ifdef __GXX_EXPERIMENTAL_CXX0X__
#include <array>
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <forward_list>
#include <future>
#include <initializer_list>
#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#endif

#include <array>

using namespace std;

int main ()
{
	double x;
	while( cin >> x )
	{
		cout <<(int) ( pow ( x  , 2.0 )/(2*9.8) + 5 +5-(1e-10)) / 5 << endl;
	}
}

C++: #include<iostream>

int main(){
  int i;
  double v,t,h;

  while(std::cin >> v){
    t = v / 9.8;
    h = 4.9 * t * t;
    for(i=2;h>5.0;i++){
      h -= 5.0;
    }
    std::cout << i << std::endl;
  }
}

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

using namespace std;

int main()
{
    double v;

    while (scanf("%lf", &v) != EOF) {
        double ans = (v*v/98);
        if (v*v <= 49.0000000) {
            puts("1");
        } else if (ans - (int)ans < 0.00000000001) {
            printf("%d\n", (int)ans + 1);
        } else {
            printf("%d\n", (int)ans + 2);
        }

    }

    return 0;
}

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

int main(){
	float in, y;
	while(cin>>in){
		y = (in*in)/(19.6);
		cout<< (int) ceil((y+5.0)/5.0)<<endl;
	}
	return 0;
}

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

int main()
{
  double v, y;

  while (cin >> v){
    double t = 0;
    int floor = 1;
    while (9.8 * t < v) t += 0.1;
    y = 4.9 * t * t;
    for (; (floor * 5) - 5 < y; floor++){}
    printf("%d\n", floor);
  }
}

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

double v;

int main() {
  while (1) {
    if (scanf("%lf", &v) != 1) return 0;
    
    int n = 1;
    while (1) {
      double h = 5*n-5;
      if (sqrt(h/4.9)*9.8 >= v) break;
      ++n;
    }

    printf("%d\n", n);
  }
}

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

int main(){
    double v;
    double y;
    int n = 1;

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

    }

    return 0;
}

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

using namespace std;
/*
	v = 9.8t
	y = 4.8t^2
	割れる速度になるtを求め、その時間でどのくらいの距離になるか計算する。
*/
int main() {
	double v;

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

		int N = static_cast<int>(ceil(y / 5)) + 1;

		cout << N << endl;
	}
}

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

//0024
int main(){
	double v;
	
	while(cin >> v){
		double t=v/9.8;		//g=9.8
		double h=4.9*t*t;	// (1/2) * g * t^2
				
		//5*f-5 > h;
		double f = (h+5)/5;
		cout << ceil(f) << endl;
	}
	return 0;
}