hdu 5003 Osu!

题目大意：按照要求计算和。

解题思路：水题。

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>using namespace std;const int maxn = 55;int n;
double p[maxn];bool cmp (const double &a, const double& b) {return a > b;
}int main () {int cas;scanf("%d", &cas);while (cas--) {scanf("%d", &n);for (int i = 0; i < n; i++)scanf("%lf", &p[i]);sort(p, p + n, cmp);double ans = 0;for (int i = 0; i < n; i++)ans += pow(0.95, i) * p[i];printf("%.10lf\n", ans);}return 0;
}