From c588e3de53bc74781fb7283e097ea258c9a8c203 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E5=90=B4=E9=98=B4=E5=A4=A9?= <overcast404@163.com> Date: Thu, 21 Mar 2024 11:15:49 +0000 Subject: [PATCH] =?UTF-8?q?docs:=20create=20=E7=AE=97=E6=B3=95/=E6=95=B0?= =?UTF-8?q?=E7=BB=84?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- 算法/数组.md | 175 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 算法/数组.md diff --git a/算法/数组.md b/算法/数组.md new file mode 100644 index 0000000..dd94605 --- /dev/null +++ b/算法/数组.md @@ -0,0 +1,175 @@ +--- +title: 数组 +description: +published: true +date: 2024-03-21T11:15:46.175Z +tags: 算法 +editor: markdown +dateCreated: 2024-03-21T11:15:46.175Z +--- + +# 二分法 +```ts +function search(nums: number[], target: number): number { + let left:number = 0; + let right:number = nums.length - 1; + while (left <= right) { + let mid:number = left + ((right - left) >> 1); + if (nums[mid] < target) { + left = mid + 1; + } else if (nums[mid] > target) { + right = mid - 1; + } else { + return mid; + } + } + return -1; +}; +``` +# 移除元素 +给你一个数组 nums 和一个值 val,你需要 原地 移除所有数值等于 val 的元素,并返回移除后数组的新长度。 +```ts +function removeElement(nums: number[], val: number): number { + let fast: number = 0, slow: number = 0; + while (fast < nums.length) { + if (nums[fast] !== val) { + nums[slow++]=nums[fast] + } + fast++; + } + return slow; +}; +``` +# 有序数组的平方 +给你一个按 非递减顺序 排序的整数数组 nums,返回 每个数字的平方 组成的新数组,要求也按 非递减顺序 排序。 + +示例 1: + +输入:nums = [-4,-1,0,3,10] +输出:[0,1,9,16,100] +解释:平方后,数组变为 [16,1,0,9,100],排序后,数组变为 [0,1,9,16,100] +示例 2: + +输入:nums = [-7,-3,2,3,11] +输出:[4,9,9,49,121] +```ts +function sortedSquares(nums: number[]): number[] { + let resArr: number[] = []; + let i: number = 0, j: number = nums?.length - 1; + while (i <= j) { + if (Math.abs(nums[i]) >= nums[j]) { + resArr.unshift(nums[i] ** 2) + i++; + } else { + resArr.unshift(nums[j] ** 2) + j--; + } + } + return resArr; +}; +``` +# 长度最小的子数组 +给定一个含有 n 个正整数的数组和一个正整数 s ,找出该数组中满足其和 ≥ s 的长度最小的 连续 子数组,并返回其长度。如果不存在符合条件的子数组,返回 0。 + +示例: + +输入:s = 7, nums = [2,3,1,2,4,3] +输出:2 +解释:子数组 [4,3] 是该条件下的长度最小的子数组。 +```ts +function minSubArrayLen(target: number, nums: number[]): number { + let res: number = nums.length + 1; + let sum: number = 0; + let i: number = 0; + for (let j = 0; j < nums?.length; j++) { + sum += nums[j]; + if (sum >= target) { + while (sum - nums[i] >= target) { + sum -= nums[i++]; + } + res = Math.min(res, j - i + 1); + } + } + return res === nums.length + 1 ? 0 : res; +}; +``` +# 螺旋矩阵II +给定一个正整数 n,生成一个包含 1 到 n^2 所有元素,且元素按顺时针顺序螺旋排列的正方形矩阵。 + +示例: + +输入: 3 输出: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ] ] +```ts +function generateMatrix(n: number): number[][] { + let di: number = 0; + const res: number[][] = new Array(n).fill(1).map(i => new Array(n)); + let num = 1; + while (di <= n >> 1) { + for (let j: number = di; j < n - di - 1; j++) { + res[di][j] = num++; + } + for (let j: number = di; j < n - di - 1; j++) { + res[j][n - di - 1] = num++; + } + for (let j: number = n - di - 1; j > di; j--) { + res[n - di - 1][j] = num++; + } + for (let j: number = n - di - 1; j > di; j--) { + res[j][di] = num++; + } + di++ + } + if (n % 2 === 1) { + res[di - 1][di - 1] = num; + } + return res; +}; +``` +# 三数之和 +给你一个包含 n 个整数的数组 nums,判断 nums 中是否存在三个元素 a,b,c ,使得 a + b + c = 0 ?请你找出所有满足条件且不重复的三元组。 + +注意: 答案中不可以包含重复的三元组。 + +示例: + +给定数组 nums = [-1, 0, 1, 2, -1, -4], + +满足要求的三元组集合为: [ [-1, 0, 1], [-1, -1, 2] ] +```ts +function threeSum(nums: number[]): number[][] { + nums.sort((a, b) => a - b); + let length = nums.length; + let left: number = 0, + right: number = length - 1; + let resArr: number[][] = []; + for (let i = 0; i < length; i++) { + if (nums[i]>0) { + return resArr; //nums经过排序后,只要nums[i]>0, 此后的nums[i] + nums[left] + nums[right]均大于0,可以提前终止循环。 + } + if (i > 0 && nums[i] === nums[i - 1]) { + continue; + } + left = i + 1; + right = length - 1; + while (left < right) { + let total: number = nums[i] + nums[left] + nums[right]; + if (total === 0) { + resArr.push([nums[i], nums[left], nums[right]]); + left++; + right--; + while (nums[right] === nums[right + 1]) { + right--; + } + while (nums[left] === nums[left - 1]) { + left++; + } + } else if (total < 0) { + left++; + } else { + right--; + } + } + } + return resArr; +}; +``` \ No newline at end of file