poj2955(区间dp)

#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <queue>
#include <cstdlib>
#include <stack>
#include <vector>
#include <set>
#include <map>
#define LL long long
#define mod 100000000
#define inf 0x3f3f3f3f
#define eps 1e-9
#define N 100010
#define FILL(a,b) (memset(a,b,sizeof(a)))
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
using namespace std;
int dp[110][110];
char str[110];
bool judge(int i,int j)
{
    return (str[i]==‘(‘&&str[j]==‘)‘)||(str[i]==‘[‘&&str[j]==‘]‘);
}
int dfs(int l,int r)
{
    if(dp[l][r]!=-1)return dp[l][r];
    if(l>=r)return 0;
    int temp=dfs(l+1,r);
    for(int i=l+1;i<=r;i++)
    {
        if(judge(l,i))
            temp=max(temp,dfs(l+1,i-1)+dfs(i+1,r)+2);
    }
    return dp[l][r]=temp;
}
int main()
{
    int n;
    while(scanf("%s",str+1)>0)
    {
        if(strcmp(str+1,"end")==0)break;
        FILL(dp,-1);n=strlen(str+1);
        printf("%d\n",dfs(1,n));
    }
}