POJ2955 Brackets

#include <cstdio>
#include <algorithm>
#include <cstring>
using namespace std;
int f[100+10][100+10];
char s[100+10];

int main()
{
    while(scanf("%s",s+1)&&s[1]!=‘e‘){
        memset(f,0,sizeof(f));
        int n=strlen(s+1);
        for (int len=2;len<=n;len++){
            for (int l=1;l<=n-len+1;l++){
                int r=l+len-1;
                if (s[r]==‘)‘&&s[l]==‘(‘) f[l][r]=f[l+1][r-1]+2;
                if (s[r]==‘]‘&&s[l]==‘[‘) f[l][r]=f[l+1][r-1]+2;
                for (int k=l;k<r;k++){
                    f[l][r]=max(f[l][k]+f[k+1][r],f[l][r]);
                }
            }
        }
        printf("%d\n",f[1][n]);
    }
    return 0; 
}