poj 1159 Palindrome

#include <stdio.h>
#include <string.h>

const int MAX_N = 5000 + 10;
int dp[MAX_N][MAX_N];
char A[MAX_N];
int Max(int a, int b) { return a > b ? a : b; }

int Min( int i, int j )
{
    if ( dp[i][j] != -1 )
        return dp[i][j];

    if ( i == j )
        return dp[i][j] = 0;
    else
    if ( i > j )
        return dp[i][j] = 0;
    else
    if ( A[i] == A[j] )
        return dp[i][j] = Min(i+1, j-1);
    else
        return dp[i][j] =  1 + Max( Min(i+1, j), Min(i, j-1) );    
}

int main()
{
    int n, ans;

    scanf( "%d %s", &n, A );

    memset( dp, -1, sizeof(dp) );
    ans = Min( 0, n-1 );
    printf( "%d\n", ans );

    return 0;
}