POJ 2955 区间DP Brackets

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <algorithm>
 5 using namespace std;
 6 
 7 const int maxn = 100 + 10;
 8 
 9 int n;
10 char s[maxn];
11 int d[maxn][maxn];
12 
13 bool inline match(char c1, char c2)
14 {
15     if(c1 == ‘[‘ && c2 == ‘]‘) return true;
16     if(c1 == ‘(‘ && c2 == ‘)‘) return true;
17     return false;
18 }
19 
20 int main()
21 {
22     while(scanf("%s", s) == 1 && s[0] != ‘e‘)
23     {
24         n = strlen(s);
25         for(int i = 0; i + 1 < n; i++)
26         {
27             if(match(s[i], s[i+1])) d[i][i+1] = 2;
28             else d[i][i+1] = 0;
29         }
30 
31         for(int l = 3; l <= n; l++)
32         {
33             for(int i = 0; i + l - 1 < n; i++)
34             {
35                 int j = i + l - 1;
36                 d[i][j] = 0;
37                 if(match(s[i], s[j])) d[i][j] = d[i+1][j-1] + 2;
38                 for(int k = i; k < j; k++)
39                     d[i][j] = max(d[i][j], d[i][k] + d[k+1][j]);
40             }
41         }
42 
43         printf("%d\n", d[0][n-1]);
44     }
45 
46     return 0;
47 }