算法竞赛入门经典——训练指南

#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;

long long C[1000010], M, a;
int main() {
    int n;
    while (~scanf("%d", &n)) {
        C[0] = 0;
        for (int i = 1; i <= n; i++) {
            scanf("%lld", &a);
            C[i] = C[i-1]+a;
        }
        M = C[n]/n;
        for (int i = 1; i < n; i++) C[i] -= i*M;
        sort(C, C+n);
        long long ans = 0, x = C[n/2];
        for (int i = 0; i < n; i++) ans += abs(x-C[i]);
        cout<<ans<<endl;
    }
}