[CQOI2007][BZOJ1260] 涂色paint

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<cmath>
#include<vector>
using namespace std;
char s[55];
int len,j,f[55][55];
int main()
{
    scanf("%s",s+1);
    len=strlen(s+1);
    memset(f,127,sizeof(f));
    for (int i=1;i<=len;i++) f[i][i]=1;
    for (int l=1;l<len;l++)
        for (int i=1;i<len;i++)
        {
            j=i+l;
            if (j>len) break;
            if (s[i]==s[j])
            {
                f[i][j]=min(f[i+1][j],f[i][j-1]);
                f[i][j]=min(f[i][j],f[i+1][j-1]+1);
            }
            else for (int k=i;k<j;k++) f[i][j]=min(f[i][j],f[i][k]+f[k+1][j]);
        }
    printf("%d",f[1][len]);
    return 0;
}