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()];
}
}