poj2955——括号匹配

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
char c[105];
int f[105][105];
bool p(char x,char y)
{
	if((x==‘(‘&&y==‘)‘)||(x==‘[‘&&y==‘]‘))return true;
	else return false;
}
int main()
{
	while(1)
	{
		gets(c);
		if(c[0]==‘e‘)return 0;
		memset(f,0,sizeof f);
		int len=strlen(c);
		for(int i=len-1;i>=0;i--)
			for(int j=i+1;j<len;j++)
			{
				for(int k=i;k<=j-1;k++)
					f[i][j]=max(f[i][j],f[i][k]+f[k+1][j]);//+
				if(p(c[i],c[j]))
					f[i][j]=max(f[i][j],f[i+1][j-1]+2);
//				printf("%d-%d:%d\n",i,j,f[i][j]);
			}
		printf("%d\n",f[0][len-1]);
	}
}