BZOJ 3253 Fence Repair 哈夫曼树 水题

http://poj.org/problem?id=3253

这道题约等于合并果子，但是通过这道题能够看出来哈夫曼树是什么了。

 #include<cstdio>
 #include<cstring>
 #include<algorithm>
 #include<cmath>
 #include<iostream>
 #include<queue>
 using namespace std;
 #define LL long long
 const int maxn=;
 int n;
 priority_queue< LL,vector<LL>,greater< LL > >q;
 int main(){
     while(~scanf("%d",&n)){
         LL x,y;
         for(int i=;i<=n;i++){scanf("%lld",&x);q.push(x);}
         LL ans=;
         while(!q.empty()){
             x=q.top();q.pop();
             if(q.empty())continue;
             y=q.top();q.pop();
             ans+=x+y;
             q.push(x+y);
         }
         printf("%lld\n",ans);
         while(!q.empty())q.pop();
     }
     return ;
 }