POJ3253 Haffman

 1 //Memory: 316K        Time: 16MS
 2 #include <iostream>
 3 #include <cstring>
 4 #include <cstdio>
 5 #include <queue>
 6 
 7 using namespace std;
 8 
 9 int n;
10 int l;
11 priority_queue <int, vector<int>, greater<int>> q;
12 
13 int main()
14 {
15     while ( !q.empty() ) q.pop();
16     scanf("%d", &n);
17     for (int i = 0; i < n; i++) {
18         scanf("%d", &l);
19         q.push(l);
20     }
21     long long ans = 0;
22     while ( q.size() >= 2 ) {
23         int a = q.top();
24         q.pop();
25         int b = q.top();
26         q.pop();
27         ans += (a + b);
28         q.push(a + b);
29     }
30     printf("%lld\n", ans);
31     return 0;
32 }