public class Solution {
    public boolean isInterleave(String s1, String s2, String s3) {
        int len1=s1.length();
        int len2=s2.length();
        int len3=s3.length();
        if(len3!=len1+len2)
            return false;
        boolean[][] res=new boolean[len1+1][len2+1];
        res[0][0]=true;
        boolean flag=true;
        for(int l=0;l