27. 移除元素

27. 移除元素

代码

javascript

// 27. 移除元素：https://leetcode.cn/problems/remove-element/description/
// 输入：nums = [3,2,2,3], val = 3
// 输出：2, nums = [2,2,_,_]

export function removeElement (nums, val) {
  let left = 0
  let right = nums.length
  while (left < right) {
    if (nums[left] === val) {
      nums[left] = nums[right - 1]
      right--
    } else {
      left++
    }
  }
  return left
}

typescript

// 27. 移除元素：https://leetcode.cn/problems/remove-element/description/
// 输入：nums = [3,2,2,3], val = 3
// 输出：2, nums = [2,2,_,_]

export function removeElement (nums: number[], val: number): number {
  let left = 0
  let right = nums.length
  while (left < right) {
    if (nums[left] === val) {
      nums[left] = nums[right - 1]
      right--
    } else {
      left++
    }
  }
  return left
}

测试代码

test

import { expect, test } from 'vitest'
import { removeElement } from './typescript.ts'
import { removeElement as removeElementJs } from './javascript.js'

test(`removeElement`, () => {
  const nums = [3,2,2,3]
  const resNums = [2,2]
  const size = removeElement(nums, 3)
  let flag = true
  for (let i = 0; i < size; i++) {
    if (nums[i] !== resNums[i]) {
      flag = false
    }
  }
  expect(size).toBe(2)
  expect(flag).toBe(true)
})

test(`removeElementJs`, () => {
  const nums = [0,1,2,2,3,0,4,2]
  const resNums = [0,1,4,0,3]
  const size = removeElementJs(nums, 2)
  let flag = true
  for (let i = 0; i < size; i++) {
    if (nums[i] !== resNums[i]) {
      flag = false
    }
  }
  expect(size).toBe(5)
  expect(flag).toBe(true)
})