CSES-1161 Stick Divisions

#include <bits/stdc++.h>
using namespace std;
 
#define pb push_back
#define fi first
#define se second
#define INF LONG_LONG_MAX/1000
#define WA() cin.tie(0)->sync_with_stdio(0);
#define all(x) (x).begin(), (x).end()
#define int long long
#define PII pair<int, int>
 
signed main() { WA();
    int n, x, t, sum = 0; cin >> x >> n;
    priority_queue<int, vector<int>, greater<int>> pq;
    while (n--) cin >> t, pq.push(t);
    while (pq.size() != 1) {
        int a = pq.top(); pq.pop();
        int b = pq.top(); pq.pop();
        sum += a+b;
        pq.push(a+b);
    }
    cout << sum;
}