POJ 1159 Palindrome(DP)

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>

using namespace std;

char save[5005];
char res[5005];
short dp[5005][5005];
int main()
{
    int n;
    while(scanf("%d",&n)!=EOF)
    {
        save[0]='#';
        scanf("%s",save+1);
        for(int i=n;i>=1;i--)
        res[n-i+1]=save[i];
        res[0]='@';
        memset(dp,0,sizeof dp);

        for(int i=1;i<=n;i++)
        {
            for(int j=1;j<=n;j++)
            {
                if(save[i]==res[j])
                {
                    dp[i][j]=dp[i-1][j-1]+1;
                }
                else dp[i][j]=max(dp[i-1][j],dp[i][j-1]);
            }
        }

        printf("%d\n",n-dp

);
    }
    return 0;
}