BZOJ 1724 USACO 2006 Nov. 切割木板

 1 #include<cstdio>
 2 #include<algorithm>
 3 #include<queue>
 4 using namespace std;
 5 int n;
 6 long long ans=0;
 7 struct cmp{
 8     bool operator() (const int a,const int b)const{return a>b;}
 9 };
10 priority_queue<int,vector<int>,cmp>a;
11 void read(int &k){
12     int f=1; k=0; char c=getchar();
13     while (c<'0'||c>'9')c=='-'&&(f=-1),c=getchar();
14     while ('0'<=c&&c<='9')k=k*10+c-'0',c=getchar();
15     k*=f;
16 }
17 int main(){
18     read(n);
19     for (int i=1;i<=n;i++){
20         int x; read(x);
21         a.push(x);
22     }
23     for (int i=1;i<n;i++){
24         int x,y;
25         x=a.top(); a.pop();
26         y=a.top(); a.pop();
27         ans+=x+y; a.push(x+y);
28     }
29     printf("%lld",ans);
30     return 0;
31 }