[poj2955]Brackets 括号最大匹配

 1 #include<cmath>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<cstdlib>
 5 #include<iostream>
 6 #include<algorithm>
 7 #define APART puts("----------------------")
 8 #define debug 1
 9 #define FILETEST 1
10 #define inf 2010
11 #define ll long long
12 #define ha 998244353
13 #define INF 0x7fffffff
14 #define INF_T 9223372036854775807
15 #define DEBUG printf("%s %d\n",__FUNCTION__,__LINE__)
16 
17 namespace chino{
18 
19 const char key[] = "end";
20 
21 inline void setting(){
22 #if FILETEST
23     freopen("_test.in", "r", stdin);
24     freopen("_test.me.out", "w", stdout);
25 #endif
26     return;
27 }
28 
29 inline int read(){
30     char c = getchar(), up = c; int num = 0;
31     for(; c < ‘0‘ || c > ‘9‘; up = c, c = getchar());
32     for(; c >= ‘0‘ && c <= ‘9‘; num = (num << 3) + (num << 1) + (c ^ ‘0‘), c = getchar());
33     return  up == ‘-‘ ? -num : num;
34 }
35 
36 char s[inf];
37 int dp[inf][inf];
38 
39 inline bool check(int a, int b){
40     return s[a] == ‘(‘ ? 
41         s[b] == ‘)‘ :
42     s[b] == ‘]‘;
43 }
44 
45 inline int main(){
46     while(true){
47         scanf("%s", s + 1);
48         if(strcmp(key, s + 1) == 0)
49             break;
50         int n = strlen(s + 1);
51         for(int i = 2; i <= n; i++){
52             for(int j = i - 1; j; j--){
53                 dp[j][i] = dp[j + 1][i];
54                 if(s[j] == ‘)‘ || s[j] == ‘]‘)
55                     continue;
56                 for(int k = j + 1; k <= i; k++){
57                     if(check(j, k))
58                         dp[j][i] = std::max (dp[j][i] , dp[j + 1][k - 1] + dp[k + 1][i] + 2);
59                 }
60             }
61         }
62         printf("%d\n", dp[1][n]);
63     }
64     return 0;
65 }
66 
67 }//namespace chino
68 
69 int main(){return chino::main();}