#include <bits/stdc++.h>   using namespace std;   template <class T>   void in(T &x) {     x = 0;     bool flag = 0;     char c = getchar();     while (c <  0  || c >  9 ) {       if (c ==  - ) flag = 1;       c = getchar();     }     while (c >=  0  && c <=  9 ) {       x = (x << 3) + (x << 1) + (c ^ 48);       c = getchar();     }     if (flag) x = -x;   }   priority_queue<long long, vector<long long>, greater<long long> > q;   long long n, x, ans;   signed main() {     in(n);     for (register long long i = 1; i <= n; ++i) {       in(x);       q.push(x);       long long tmp = q.top();       if (x > tmp) ans += x - tmp, q.pop(), q.push(x);     }     printf( %lld , ans);   }   