简单题
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#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
using namespace std;
#define maxn 10006
int f[maxn];
int main()
{
//freopen("t.txt", "r", stdin);
int n;
scanf("%d", &n);
for (int i = 0; i < n; i++)
scanf("%d", &f[i]);
sort(f, f + n);
long long ans = 0, sum = 0;
for (int i = 1; i < n; i++)
{
sum += ((long long)(f[i] - f[i - 1])) * i;
ans += sum;
}
printf("%lld\n", ans * 2);
return 0;
}