今天是練習cpe的What is the Probability題目
#include <bits/stdc++.h>
using namespace std;
int main()
{
int S,N,i;
double p;
cin >> S;
while(S--)
{
cin >> N >> p >> i;
if(p == 0)
{
cout << 0.000 <<endl;
continue;
}
double first = pow(1.0 - p, i-1)*p;
double fall = pow(1.0 - p, N);
cout << fixed << setprecision(4) << first / (1.0 - fall) << endl ;
}
return 0;
}