Common Subsequence 1458 pku

#include<iostream>

#include<string.h>

using namespace std;

int exportMax(int a,int b)

{

    return a>b? a:b;

}

int opt[1010][1010];

int main()

{

    char str1[1010],str2[1010];

    while(cin>>str1+1>>str2+1)

    {

         int len1=strlen(str1+1);

         int len2=strlen(str2+1);

         memset(opt,0,sizeof(opt));

         for(int i=1;i<=len1;i++)

         {

             for(int j=1;j<=len2;j++)

             {

                if(str1[i]==str2[j])

                {

                    opt[i][j]=opt[i-1][j-1]+1;

                }

                else

                {

                    opt[i][j]=exportMax(opt[i-1][j],opt[i][j-1]);

                }

             }

         }

         cout<<opt[len1][len2]<<endl;

    }

}