func_code_string: #include <bits/stdc++.h>   using namespace std;   long long n, m, a[1000001], mx[1000001], cnt, maxi, ans;   int main() {     cin >> n;     for (long long i = 1; i <= n; ++i) {       cin >> a[i];       mx[i] = -1;       for (long long j = 1; j <= a[i]; ++j) {         long long k;         cin >> k;         mx[i] = max(mx[i], k);       }     }     for (long long i = 1; i <= n; ++i) {       maxi = max(maxi, mx[i]);     }     for (long long i = 1; i <= n; ++i) {       cnt += (maxi - mx[i]) * a[i];     }     cout << cnt;   }   