LOTT - Xổ số
Tác giả: ll931110
Ngôn ngữ: C++
#include <algorithm>
#include <bitset>
#include <cmath>
#include <cstring>
#include <deque>
#include <fstream>
#include <iostream>
#include <iterator>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <vector>
typedef long long ll;
using namespace std;
int n;
int main()
{
// freopen("lott.in","r",stdin);
// freopen("lott.ou","w",stdout);
string s;
while (1)
{
cin >> s;
if (s == "[END]") break;
cin >> n;
// cout << n;
double c = 1.0;
for (int i = 0; i < 5; i++) c*= (5 * n - i) / (i + 1.0) * 1.0;
double c3 = 5.0 * n * (5 * n - 5) * (5 * n - 6);
double c4 = n * (5 * n - 5) * 5.0;
double c5 = n * 1.0;
printf("%.9lf\n", (c3 + c4 + c5)/c);
};
};