BZOJ 1260 [CQOI2007]涂色paint

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;
char s[55];
int f[55][55];
int main() {
    scanf("%s", s);
    int n = strlen(s);
    memset(f, 0x3f, sizeof(f));
    for(int i = 0; i < n; i++) f[i][i] = 1;
    for(int len = 2; len <= n; len++) {
        for(int l = 0, r = len - 1; r < n; l++, r++) {
            if(s[l] == s[r]) {
                f[l][r] = min(f[l + 1][r], f[l][r - 1]);
                f[l][r] = min(f[l][r], f[l + 1][r - 1] + 1);
            }
            else for(int i = l; i < r; i++)
              f[l][r] = min(f[l][r], f[l][i] + f[i + 1][r]);
        }
    }
    printf("%d\n", f[0][n - 1]);
    return 0;
}