Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.
For example,
Given:
s1 = "aabcc"
,
s2 = "dbbca"
,
When s3 = "aadbbcbcac"
, return true.
When s3 = "aadbbbaccc"
, return false.
public class Solution { public boolean isInterleave(String s1, String s2, String s3) { if (s1.length()+s2.length() != s3.length()) { return false; } boolean[][] res = new boolean[s1.length()+1][s2.length()+1]; res[0][0] = true; for (int i = 1; i <= s1.length() && s1.charAt(i-1) == s3.charAt(i-1); i++) { res[i][0] = true; } for (int i = 1; i <= s2.length() && s2.charAt(i-1) == s3.charAt(i-1); i++) { res[0][i] = true; } for (int i = 1; i <= s1.length(); i++) { for (int j = 1; j <= s2.length(); j++) { char charAt = s3.charAt(i+j-1); if (s1.charAt(i-1)==charAt && res[i-1][j]) { res[i][j] = true; } if (s2.charAt(j-1)==charAt && res[i][j-1]) { res[i][j] = true; } } } return res[s1.length()][s2.length()]; } }