From 870da93b064c0df432d6343f87439505d546b212 Mon Sep 17 00:00:00 2001
From: Shivang-Agarwal11 <65328598+Shivang-Agarwal11@users.noreply.github.com>
Date: Thu, 1 Oct 2020 14:50:58 +0530
Subject: [PATCH] Update LowestCommenSubsequence.py

This is the LCS program using recursion.
---
 LowestCommenSubsequence.py | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/LowestCommenSubsequence.py b/LowestCommenSubsequence.py
index e3fced4..14bf547 100644
--- a/LowestCommenSubsequence.py
+++ b/LowestCommenSubsequence.py
@@ -1,20 +1,14 @@
-def lcs(X, Y): 
-    # find the length of the strings 
-    m = len(X) 
-    n = len(Y) 
+def lcs(X, Y, m, n): 
   
-    # declaring the array for storing the dp values 
-    L = [[None]*(n - 1) for i in range(m - 1)] 
+    if m == 0 or n == 0: 
+       return 0; 
+    elif X[m-1] == Y[n-1]: 
+       return 1 + lcs(X, Y, m-1, n-1); 
+    else: 
+       return max(lcs(X, Y, m, n-1), lcs(X, Y, m-1, n)); 
   
-    for i in range(m + 1): 
-        for j in range(n + 1): 
-            if i == 0 or j == 0 : 
-                L[i][j] = 0
-            elif X[i-1] == Y[j-1]: 
-                L[i][j] = L[i-1][j-1]+1
-            else: 
-                L[i][j] = max(L[i-1][j], L[i][j-1]) 
-    return L[m][n] 
+  
+# Driver program to test the above function 
 X = "AGGTAB"
 Y = "GXTXAYB"
-print("Length of LCS is ", lcs(X, Y))
+print ("Length of LCS is ", lcs(X , Y, len(X), len(Y)) )