Create LCS_Top_Down.java

Author: mohitsingla123

Longest Common Subsequence/LCS_Top_Down.java

@@ -0,0 +1,41 @@
+// solving lcs with top down approch
+
+public class HelloWorld{
+
+     public static void main(String []args){
+        String a = "aeiou";
+        String b = "asdertiop";
+        int lena = a.length();
+        int lenb = b.length();
+        
+        int[][] arr = new int[lena + 1][lenb + 1];
+        int i ,j;
+        for (i =0;i<=lena;i++)
+        {
+            for(j =0;j<=lenb;j++)
+            {
+                if(i==0 || j == 0)
+                {
+                   arr[i][j] = 0;
+                }
+            }
+        }
+        
+        for(i = 1; i<=lena;i++)
+        {
+            for (j = 1; j<=lenb; j++)
+            {
+                if(a.charAt(i-1) == b.charAt(j-1))
+                {
+                    arr[i][j] = 1 + arr[i-1][j-1];
+                }
+                else
+                {
+                    arr[i][j] = Math.max(arr[i-1][j] , arr[i][j-1]);
+                }
+            }
+        }
+        
+        System.out.println(arr[lena][lenb]);
+     }
+}