#include <cstdio> #include <iostream> #include <cstring> #include <string> using namespace std; char s[105]; int dp[105][105]; const char end[4] = "end"; int main () { while(scanf("%s", s) != EOF && strcmp(s, end)) { int len = strlen(s); for(int i=0; i<len-1; i++) { dp[i][i+1] = 2*(s[i]==‘(‘ && s[i+1]==‘)‘ || s[i]==‘[‘ && s[i+1]==‘]‘); } for(int step=2; step<len; step++) { for(int i=0; i+step<len; i++) { int j = i+step; //删去不必要的字符 if(s[i]!=‘(‘ && s[i]!=‘[‘) { dp[i][j] = dp[i+1][j]; } else if(s[j]!=‘)‘ && s[j]!=‘]‘) { dp[i][j] = dp[i][j-1]; } else { dp[i][j]=0; if(s[i]==‘(‘ && s[j]==‘)‘ || s[i]==‘[‘ && s[j]==‘]‘) { dp[i][j] = dp[i+1][j-1]+2; } for(int k=i; k<j; k++) { dp[i][j] = max(dp[i][j], dp[i][k] + dp[k+1][j]); } } } } printf("%d\n", dp[0][len-1]); } return 0; }
原文:http://www.cnblogs.com/AcIsFun/p/5327209.html