POJ3253-Fence Repair

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <algorithm>
 4 using namespace std;
 5 
 6 #define MAX_N 30000
 7 
 8 int N, L[MAX_N];
 9 
10 
11 int solve()
12 {
13     long long ans = 0;
14     //直到计算到木板为1块为止
15     while (N > 1)
16     {
17         //求出最短板mii1和次短板mii2
18         int mii1 = 0, mii2 = 1;
19         if (L[mii1] > L[mii2]) swap(mii1, mii2);
20 
21         for (int i = 2; i < N; i++)
22         {
23             if (L[i] < L[mii1])
24             {
25                 mii2 = mii1;
26                 mii1 = i;
27             }
28             else if (L[i] < L[mii2])
29             {
30                 mii2 = i;
31             }
32         }
33 
34         //将两块木板合并
35         int t = L[mii1] + L[mii2];
36         ans += t;
37 
38         if (mii1 == N-1) swap(mii1, mii2);
39         L[mii1] = t;
40         L[mii2] = L[N-1];
41         N--;
42     }
43 
44     printf("%lld\n", ans);
45 }
46 
47 int main()
48 {
49     cin >> N;
50     for (int i = 0; i < N; i++)
51         cin >> L[i];
52     solve();
53     return 0;
54 }