Merge pull request #95 from sanskar28/master

Updated Common Child in Java

README.md

@@ -35,7 +35,7 @@ in C++, Java, Python and Javascript.
 ||[Making Anagrams](https://www.hackerrank.com/challenges/ctci-making-anagrams/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/making_anagrams.cpp)|[Done](/String%20Manipulation/MakingAnagrams.java)|[Done](/String%20Manipulation/MakingAnagrams.py)||
 ||[Sherlock and Valid String](https://www.hackerrank.com/challenges/sherlock-and-valid-string/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/sherlock_and_valid_string.cpp)||[Done](/String%20Manipulation/SherlockValidString.py)||
 ||[Special String Again](https://www.hackerrank.com/challenges/special-palindrome-again/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/special_palindrome_again.cpp)||[Done](/String%20Manipulation/SpecialStringAgain.py)||
-||[Common Child](https://www.hackerrank.com/challenges/common-child/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/common_child.cpp)||[Done](/String%20Manipulation/CommonChild.py)||
+||[Common Child](https://www.hackerrank.com/challenges/common-child/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/common_child.cpp)|[Done](/String%20Manipulation/CommonChild.java)|[Done](/String%20Manipulation/CommonChild.py)||
 ||[Alternating Characters](https://www.hackerrank.com/challenges/alternating-characters/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=strings)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/String%20Manipulation/alternating_characters.cpp)|[Done](/String%20Manipulation/alternating_characters.java)|[Done](/String%20Manipulation/AlternatingCharacters.py)||
 |Greedy Algorithms||||||
 | |[Luck Balance](https://www.hackerrank.com/challenges/luck-balance/problem?h_l=interview&playlist_slugs%5B%5D=interview-preparation-kit&playlist_slugs%5B%5D=greedy-algorithms)|[Done](https://github.com/maze-runnar/interview-preparation-kit/blob/master/Greedy%20Algorithm/luck_balance.cpp)||[Done](/Greedy%20Algorithm/LuckBalance.py)||

String Manipulation/CommonChild.java

@@ -0,0 +1,39 @@
+import java.io.*;
+import java.util.*;
+import java.text.*;
+import java.math.*;
+import java.util.regex.*;
+
+public class Solution {
+
+    public static void main(String[] args) throws Exception {
+        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
+         BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
+    String s=br.readLine();
+    String s2=br.readLine();
+    int M = s.length();
+    int N = s2.length();
+
+             int[][] arr = new int[M+1][N+1];
+        for (int i = M-1; i >= 0; i--) {
+            for (int j = N-1; j >= 0; j--) {
+                if (s.charAt(i) == s2.charAt(j))
+                    arr[i][j] = arr[i+1][j+1] + 1;
+                else 
+                    arr[i][j] = Math.max(arr[i+1][j], arr[i][j+1]);
+            }
+        }
+        int i = 0, j = 0;
+        int count =0;
+        while(i < M && j < N) {
+            if (s.charAt(i) == s2.charAt(j)) {
+                count++;
+                i++;
+                j++;
+            }
+            else if (arr[i+1][j] >= arr[i][j+1]) i++;
+            else                                 j++;
+        }
+        System.out.println(count);
+    }
+}