1700 Crossing River

 1 #include <iostream> 
 2 #include <algorithm> 
 3 using namespace std;
 4 bool comp(int a,int b){
 5     return a<b;
 6 }
 7 int main(){
 8     int m,n,t[10001],i,sum;
 9     cin>>m;
10     while(m--){
11         cin>>n;
12         sum = 0;
13         for(i=0;i<n;++i)
14             cin>>t[i];
15         sort(t,t+n,comp);
16         for(i=n-1;i>2;i-=2){
17             //把t[0]和t[1]当成搬运工,最后返回到原地
18             int t1 = t[0]+2*t[1]+t[i];//最快的(即所用时间t[0])和次快的过河,然后最快的将船划回来,再次慢的和最慢的过河,然后次快的将船划回来
19             int t2 = 2*t[0]+t[i-1]+t[i];//最快的和最慢的过河,然后最快的将船划回来,再最快的和次慢的过河,然后最快的将船划回来
20             sum += t1>t2?t2:t1;
21         }
22         if(i==2) //3people left
23             sum += t[0]+t[1]+t[2];
24         else if(i==1) //2 people left
25             sum += t[1];
26         else  // 1 people left
27             sum += t[0];
28         cout<<sum<<endl;
29     }
30     return 0;
31 }