聪明的木匠 (哈夫曼树)

#include <bits/stdc++.h>
using namespace std;

priority_queue<int, vector<int>, greater<int>> Q;

int main() {
	int n, input, ans = 0;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> input;
		Q.push(input);
	}
	while (!Q.empty()) {
		int a, b;
		a = Q.top();
		Q.pop();
		if (Q.empty()) break;
		b = Q.top();
		Q.pop();
		ans += a+b;
		Q.push(a+b);
	}
	cout << ans << endl;
 	return 0;
}