Create remove_elements.py

Shorya22 · Shorya22 · commit 9106bf99f047 · 2025-08-07T00:09:51.000+05:30
diff --git a/arrays_hashing/remove_elements.py b/arrays_hashing/remove_elements.py
@@ -0,0 +1,34 @@
+# You are given an integer array nums and an integer val. Your task is to remove all occurrences of val from nums in-place.
+# After removing all occurrences of val, return the number of remaining elements, say k, such that the first k elements of nums do not contain val.
+# Note:
+# The order of the elements which are not equal to val does not matter.
+# It is not necessary to consider elements beyond the first k positions of the array.
+# To be accepted, the first k elements of nums must contain only elements not equal to val.
+# Return k as the final result.
+# Example :
+# Input: nums = [1,1,2,3,4], val = 1
+# Output: [2,3,4]
+
+# Method 1: (Brute Force)
+class Solution:
+    def removeElement(self, nums: list[int], val: int) -> int:
+        tmp = []
+        for num in nums:
+            if num == val:
+                continue
+            tmp.append(num)
+        
+        for i in range(len(tmp)):
+            nums[i] = tmp[i]
+
+        return len(tmp)    
+
+# Method 2: (Two Pointers)
+class Solution:
+    def removeElement(self, nums: list[int], val: int) -> int:
+        k = 0
+        for i in range(len(nums)):
+            if  nums[i] != val:
+                nums[k] = nums[i]
+                k += 1
+        return k
