hdu1159 Common Subsequence

#include <stdio.h>
#include <string.h>
#define MAXN 1002

int dp[MAXN][MAXN];

int main()
{
	char str1[MAXN],str2[MAXN];
	int i,j,len1,len2;
	while(scanf("%s %s",str1,str2)!=EOF)
	{
		memset(dp,0,sizeof(dp));
		len1=strlen(str1);
		len2=strlen(str2);
		for (i=1;i<=len1;i++)
		{
			for (j=1;j<=len2;j++)
			{
				if(str1[i-1]==str2[j-1])
					dp[i][j]=dp[i-1][j-1]+1;
				else
					dp[i][j]=(dp[i-1][j]>dp[i][j-1])?dp[i-1][j]:dp[i][j-1];
			}
		}
		printf("%d\n",dp[len1][len2]);
	}
	return 0;
}