Replace Elements w. Greatest Element on Right Side

Difficulty: Easy
15 / 15 test cases passed.
Runtime: 112 ms
Memory Usage: 14.8 MB

Author: YuriSpiridonov

Easy/1299.ReplaceElementswithGreatestElementonRightSide.py

@@ -0,0 +1,28 @@
+"""
+    Given an array arr, replace every element in that array with the greatest 
+    element among the elements to its right, and replace the last element with -1.
+    After doing so, return the array.
+
+    Example:
+    Input: arr = [17,18,5,4,6,1]
+    Output: [18,6,6,6,1,-1]
+"""
+#Difficulty: Easy
+#15 / 15 test cases passed.
+#Runtime: 112 ms
+#Memory Usage: 14.8 MB
+
+#Runtime: 112 ms, faster than 99.50% of Python3 online submissions for Replace Elements with Greatest Element on Right Side.
+#Memory Usage: 14.8 MB, less than 100.00% of Python3 online submissions for Replace Elements with Greatest Element on Right Side.
+
+class Solution:
+    def replaceElements(self, arr: List[int]) -> List[int]:
+        i = len(arr)-1
+        greater = -1
+        while i >= 0:
+            if arr[i] > greater:
+                arr[i], greater =  greater, arr[i]
+            else:
+                arr[i] = greater
+            i -= 1
+        return arr