Create 1331.RankTransformofanArray.py

Author: YuriSpiridonov

Easy/1331.RankTransformofanArray.py

@@ -0,0 +1,46 @@
+'''
+    Given an array of integers arr, replace each element with its rank.
+
+    The rank represents how large the element is. The rank has the 
+    following rules:
+        - Rank is an integer starting from 1.
+        - The larger the element, the larger the rank. If two elements 
+          are equal, their rank must be the same.
+        - Rank should be as small as possible.
+
+    Example:
+    Input: arr = [40,10,20,30]
+    Output: [4,1,2,3]
+    Explanation: 40 is the largest element. 10 is the smallest. 20 is 
+                 the second smallest. 30 is the third smallest.
+
+    Example:
+    Input: arr = [100,100,100]
+    Output: [1,1,1]
+    Explanation: Same elements share the same rank.
+
+    Example:
+    Input: arr = [37,12,28,9,100,56,80,5,12]
+    Output: [5,3,4,2,8,6,7,1,3]
+
+    Constraints:
+        - 0 <= arr.length <= 10^5
+        - -10^9 <= arr[i] <= 10^9
+'''
+#Difficulty: Easy
+#37 / 37 test cases passed.
+#Runtime: 340 ms
+#emory Usage: 36.2 MB
+
+#Runtime: 340 ms, faster than 66.17% of Python3 online submissions for Rank Transform of an Array.
+#Memory Usage: 36.2 MB, less than 19.18% of Python3 online submissions for Rank Transform of an Array.
+
+class Solution:
+    def arrayRankTransform(self, arr: List[int]) -> List[int]:
+        nums_indices = {}
+        sorted_array = sorted(set(arr))
+        for index, num in enumerate(sorted_array):
+            nums_indices[num] = index
+        for index, num in enumerate(arr):
+            arr[index] = 1 + nums_indices[num]
+        return arr