hdu5985[概率dp] 2016青岛icpc现场赛

#include <bits/stdc++.h>
using namespace std;
double alldead[][];
double rev[][];
double p[][];
double ans[];
int a[];
int T, n;
double fastpow(double a, int b) {
    double ret = 1.0;
    while (b) {
        if (b & ) {
            ret *= a;
        }
        a = a * a;
        b >>= ;
    }
    return ret;
}
int main() {
    scanf("%d", &T);
    while (T--) {
        scanf("%d", &n);
        for (int i = ; i <= n; i++) {
            scanf("%d%lf", &a[i], &p[i][]);
        }
        if (n == ) {
            puts("1.000000");
            continue;
        }
        for (int i = ; i <= n; i++) {
            for (int j = ; j <= ; j++) {
                p[i][j] = p[i][] * p[i][j - ];
            }
            rev[i][] = 1.0;
            alldead[i][] = 0.0;
            for (int j = ; j <= ; j++) {
                alldead[i][j] = fastpow(1.0 - p[i][j], a[i]);
                rev[i][j] = 1.0 - alldead[i][j];
            }
        }
        for (int i = ; i <= n; i++) {
            for (int j = ; j <= ; j++) {
                double tmp = ;
                for (int k = ; k <= n; k++) {
                    if (k == i) continue;
                    tmp *= alldead[k][j];
                }
                ans[i] += (rev[i][j] - rev[i][j + ]) * tmp;
            }
        }
        for (int i = ; i <= n; i++) {
            if (i != ) printf(" ");
            printf("%.6f", ans[i]);
            ans[i] = 0.0;
        } puts("");
    }
    return ;
}