糖果传递

题目描述

思路

代码

#include <cstdio>
#include <cmath>
#include <algorithm>

long long n, avg, tot, arr[1000005], ans;
inline long long int read() {
	long long s = 0, f = 1;
	char ch = getchar();
	while (ch < '0' || ch > '9') {
		if (ch == '-') f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') s = s * 10 + ch - '0',
	ch = getchar();
	return s * f;
}
int main() {
	n = read();
	for (int i = 1; i <= n; ++i) {
		arr[i] = read(), tot += arr[i];
	}
	avg = tot / n;
	for (int i = 1; i <= n; ++i) {
		arr[i] -= avg, arr[i] += arr[i - 1];
	}
	std::sort(arr + 1, arr + n + 1);
	for (int i = 1, j = n >> 1; i <= n; ++i) {
		ans += abs(arr[i] - arr[j]);
	}
	printf("%lld\n", ans);
	return 0;
}