Redcube

Author: rahulcode22

Max-GCD-Pair.py

@@ -0,0 +1,25 @@
+'''We are given an array of positive integers. Find the pair in array with maximum GCD.'''
+def maxGCDPair(arr):
+    high = max(arr)
+    n = len(arr)
+    count = [0]*(high+1)
+
+    for i in range(n):
+        count[arr[i]] = 1
+
+    counter = 0
+    #Iterating from max to 1
+    #GCD is always between MAX and 1
+    for i in range(high,0,-1):
+        j = i
+        #Iterating from curr potential GCD till it is less than max
+        while j <= high:
+            if count[j] == 1:
+                counter += 1
+            #Incrementing potential GCD by itself 2i,3i....
+            j += i
+            if counter == 2:
+                return i
+
+arr = [1,2,12,3,6]
+print maxGCDPair(arr)