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#include <bits/stdc++.h>
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using namespace std;
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const int N = 1000010;
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typedef long long LL;
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LL a[N], c[N], sum, avg, n, res;
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int main() {
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// 加快读入
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ios::sync_with_stdio(false), cin.tie(0);
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cin >> n;
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for (int i = 1; i <= n; i++) cin >> a[i], sum += a[i];
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avg = sum / n;
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// c[k]=(a[1]+a[2]+...+a[k])-k*avg
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// c[k-1]=(a[1]+a[2]+...+a[k-1])-(k-1)*avg
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// 努力找出c[k]与 c[k-1]之间的递推关系：
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// c[k]=c[k-1]+a[k]-avg
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// 所以,c数组可以通过递推得到
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for (int k = 1; k <= n; k++) c[k] = c[k - 1] + a[k] - avg;
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// 通过排序 => c[(n+1)/2] = 中位值
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sort(c + 1, c + n + 1);
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// 将x_n'放到中位值处，这样，几何含义上所有n 个位置上c1,c2,...cn到中位值的距离绝对值和最小
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for (int i = 1; i <= n; i++) res += abs(c[i] - c[(n + 1) / 2]);
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cout << res << endl;
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return 0;
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}
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