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27. Remove Element

Problem Page: https://leetcode.com/problems/remove-element/

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#
# @lc app=leetcode id=27 lang=python3
#
# [27] Remove Element
#
# https://leetcode.com/problems/remove-element/description/
#
# algorithms
# Easy (53.10%)
# Likes:    1201
# Dislikes: 1594
# Total Accepted:    2.1M
# Total Submissions: 3.9M
# Testcase Example:  '[3,2,2,3]\n3'
#
# Given an integer array nums and an integer val, remove all occurrences of val
# in nums in-place. The order of the elements may be changed. Then return the
# number of elements in nums which are not equal to val.
#
# Consider the number of elements in nums which are not equal to val be k, to
# get accepted, you need to do the following things:
#
#
# Change the array nums such that the first k elements of nums contain the
# elements which are not equal to val. The remaining elements of nums are not
# important as well as the size of nums.
# Return k.
#
#
# Custom Judge:
#
# The judge will test your solution with the following code:
#
#
# int[] nums = [...]; // Input array
# int val = ...; // Value to remove
# int[] expectedNums = [...]; // The expected answer with correct length.
# ⁠                           // It is sorted with no values equaling val.
#
# int k = removeElement(nums, val); // Calls your implementation
#
# assert k == expectedNums.length;
# sort(nums, 0, k); // Sort the first k elements of nums
# for (int i = 0; i < actualLength; i++) {
# ⁠   assert nums[i] == expectedNums[i];
# }
#
#
# If all assertions pass, then your solution will be accepted.
#
#
# Example 1:
#
#
# Input: nums = [3,2,2,3], val = 3
# Output: 2, nums = [2,2,_,_]
# Explanation: Your function should return k = 2, with the first two elements
# of nums being 2.
# It does not matter what you leave beyond the returned k (hence they are
# underscores).
#
#
# Example 2:
#
#
# Input: nums = [0,1,2,2,3,0,4,2], val = 2
# Output: 5, nums = [0,1,4,0,3,_,_,_]
# Explanation: Your function should return k = 5, with the first five elements
# of nums containing 0, 0, 1, 3, and 4.
# Note that the five elements can be returned in any order.
# It does not matter what you leave beyond the returned k (hence they are
# underscores).
#
#
#
# Constraints:
#
#
# 0 <= nums.length <= 100
# 0 <= nums[i] <= 50
# 0 <= val <= 100
#
#
#

# @lc code=start

from typing import List


class Solution:
    def removeElement(self, nums: List[int], val: int) -> int:
        s = 0

        l = len(nums)

        for f in range(l):
            if nums[f] != val:
                nums[s] = nums[f]
                s += 1

        return s

# @lc code=end
Last update: Sep 17, 2023
Created: Sep 17, 2023

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