poj2646

简单题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;

#define maxn 1005

int n;
long long sum, f[maxn], f1[maxn];

int main()
{
    //freopen("t.txt", "r", stdin);
    while (scanf("%d", &n), n)
    {
        sum = 0;
        for (int i = 0; i < n; i++)
        {
            double a;
            scanf("%lf", &a);
            f[i] = (long long)(a * 100 + 0.5);
            sum += f[i];
        }
        sort(f, f + n);
        reverse(f, f + n);
        long long a, ave;
        ave = sum / n;
        a = sum % n;
        for (int i = 0; i < n; i++)
            f1[i] = ave;
        for (int i = 0; i < a; i++)
            f1[i] += 1;
        long long ans = 0;
        for (int i = 0; i < n; i++)
            if (f[i] > f1[i])
                ans += f[i] - f1[i];
        printf("$%.2f\n", double(ans / 100.0));
    }
    return 0;
}