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Merge pull request #1590 from xiaomosimon/leetcode-dev

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Update 0704.二分法查找 JavaScript和TypeScript版本
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程序员Carl
2022-08-24 10:06:05 +08:00
committed by GitHub
parent dee5d5d95e 708c3eefdf
commit fbe1e0006e
1 changed files with 12 additions and 8 deletions
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problems/0704.二分查找.md
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@ -290,10 +290,11 @@ func search(nums []int, target int) int {
*/
var search = function(nums, target) {
// right是数组最后一个数的下标，num[right]在查找范围内，是左闭右闭区间
let left = 0, right = nums.length - 1;
let mid, left = 0, right = nums.length - 1;
// 当left=right时，由于nums[right]在查找范围内，所以要包括此情况
while (left <= right) {
let mid = left + Math.floor((right - left)/2);
// 位运算 + 防止大数溢出
mid = left + ((right - left) >> 1);
// 如果中间数大于目标值，要把中间数排除查找范围，所以右边界更新为mid-1；如果右边界更新为mid，那中间数还在下次查找范围内
if (nums[mid] > target) {
right = mid - 1; // 去左面闭区间寻找
@ -316,10 +317,11 @@ var search = function(nums, target) {
*/
var search = function(nums, target) {
// right是数组最后一个数的下标+1，nums[right]不在查找范围内，是左闭右开区间
let left = 0, right = nums.length;
let mid, left = 0, right = nums.length;
// 当left=right时，由于nums[right]不在查找范围，所以不必包括此情况
while (left < right) {
let mid = left + Math.floor((right - left)/2);
// 位运算 + 防止大数溢出
mid = left + ((right - left) >> 1);
// 如果中间值大于目标值，中间值不应在下次查找的范围内，但中间值的前一个值应在；
// 由于right本来就不在查找范围内，所以将右边界更新为中间值，如果更新右边界为mid-1则将中间值的前一个值也踢出了下次寻找范围
if (nums[mid] > target) {
@ -340,9 +342,10 @@ var search = function(nums, target) {
```typescript
function search(nums: number[], target: number): number {
let left: number = 0, right: number = nums.length - 1;
let mid: number, left: number = 0, right: number = nums.length - 1;
while (left <= right) {
let mid: number = left + Math.floor((right - left) / 2);
// 位运算 + 防止大数溢出
mid = left + ((right - left) >> 1);
if (nums[mid] > target) {
right = mid - 1;
} else if (nums[mid] < target) {
@ -359,9 +362,10 @@ function search(nums: number[], target: number): number {
```typescript
function search(nums: number[], target: number): number {
let left: number = 0, right: number = nums.length;
let mid: number, left: number = 0, right: number = nums.length;
while (left < right) {
let mid: number = left + Math.floor((right - left) / 2);
// 位运算 + 防止大数溢出
mid = left +((right - left) >> 1);
if (nums[mid] > target) {
right = mid;
} else if (nums[mid] < target) {