POJ - 3253 Fence Repair(贪心)

 1 #include <iostream>
 2 #include <algorithm>
 3 using namespace std;
 4 
 5 typedef long long LL;
 6 const int maxn=20000+10;
 7 int L[maxn];
 8 
 9 int main(){
10     int N;
11     cin>>N;
12     for(int i=0;i<N;i++) cin>>L[i];
13     LL ans=0;
14     while(N>1){
15         int temp1=0,temp2=1;
16         if(L[temp1]>L[temp2]) swap(temp1,temp2);
17         for(int i=2;i<N;i++){
18             if(L[i]<L[temp1]){
19                 temp2=temp1;
20                 temp1=i;
21             }
22             else if(L[i]<L[temp2]){
23                 temp2=i;
24             }
25         }
26         int t=L[temp1]+L[temp2];
27         ans+=t;
28         L[temp1]=t;
29         L[temp2]=L[N-1];
30         N--;
31     }
32     cout<<ans<<endl;
33     return 0;
34 }