zoj 3595 Two Sequences

#include <cstdio>#include <cstring>#include <cmath>using namespace std;int main(){ double x; int n; double a0; while (scanf("%lf %d", &a0, &n) == 2) { double ans = 0; for (int i = 0; i < n; i++) { scanf("%lf", &x); ans += x * x / 2.0 + x; } ans /= n; ans = a0 * exp(ans); printf("%lfn", ans); } return 0;}