func_code_string: #include <bits/stdc++.h>   using namespace std;   long long a[300010], po[300010], ans;   int n, p = 1e9 + 7;   int main() {     scanf( %d , &n);     for (int i = 1; i <= n; i++) scanf( %I64d , &a[i]);     sort(a + 1, a + n + 1);     po[0] = 1;     for (int i = 1; i <= n; i++) po[i] = po[i - 1] * 2 % p;     for (int i = 1; i <= n; i++)       (ans += a[i] * (p + po[i - 1] - po[n - i]) % p) %= p;     printf( %I64d n , ans);     return 0;   }   