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feat: add solutions to lc problem: No.0033
No.0033.Search in Rotated Sorted Array
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‎solution/0000-0099/0033.Search in Rotated Sorted Array/README.md

+132-57
Original file line numberDiff line numberDiff line change
@@ -54,7 +54,20 @@
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<!-- 这里可写通用的实现逻辑 -->
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二分查找。
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**方法一：二分查找**
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我们使用二分，将数组分割成 `[left, mid]`, `[mid + 1, right]` 两部分，这时候可以发现，其中有一部分一定是有序的。
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因此，我们可以根据有序的那一部分，判断 `target` 是否在这一部分中：
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- 若 `[0, mid]` 范围内的元素构成有序数组：
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- 若满足 `nums[0] <= target <= nums[mid]`，那么我们搜索范围可以缩小为 `[left, mid]`；
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- 否则，在 `[mid + 1, right]` 中查找；
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- 若 `[mid + 1, n - 1]` 范围内的元素构成有序数组：
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- 若满足 `nums[mid] < target <= nums[n - 1]`，那么我们搜索范围可以缩小为 `[mid + 1, right]`；
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- 否则，在 `[left, mid]` 中查找。
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二分查找终止条件是 `l >= r`，若结束后发现 `nums[left]` 与 `target` 不等，说明数组中不存在值为 `target` 的元素，返回 -1，否则返回下标 left。
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<!-- tabs:start -->
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@@ -65,22 +78,21 @@
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```python
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class Solution:
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def search(self, nums: List[int], target: int) -> int:
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l, r = 0, len(nums) - 1
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while l <= r:
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mid = (l + r) >> 1
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if nums[mid] == target:
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return mid
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if nums[mid] > target:
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if nums[mid] >= nums[r] and target < nums[l]:
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l = mid + 1
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n = len(nums)
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left, right = 0, n - 1
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while left < right:
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mid = (left + right) >> 1
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if nums[0] <= nums[mid]:
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if nums[0] <= target and target <= nums[mid]:
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right = mid
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else:
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r = mid - 1
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left = mid + 1
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else:
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if nums[mid] <= nums[l] and target > nums[r]:
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r = mid - 1
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if nums[mid] < target and target <= nums[n - 1]:
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left = mid + 1
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else:
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l = mid + 1
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return -1
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right = mid
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return left if nums[left] == target else -1
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```
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### **Java**
@@ -90,19 +102,25 @@ class Solution:
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```java
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class Solution {
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public int search(int[] nums, int target) {
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int l = 0, r = nums.length - 1;
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while (l <= r) {
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int mid = (l + r) >>> 1;
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if (nums[mid] == target) return mid;
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if (nums[mid] > target) {
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if (nums[mid] >= nums[r] && target < nums[l]) l = mid + 1;
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else r = mid - 1;
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int n = nums.length;
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int left = 0, right = n - 1;
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while (left < right) {
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int mid = (left + right) >> 1;
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if (nums[0] <= nums[mid]) {
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if (nums[0] <= target && target <= nums[mid]) {
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right = mid;
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} else {
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left = mid + 1;
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}
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} else {
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if (nums[mid] <= nums[l] && target > nums[r]) r = mid - 1;
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else l = mid + 1;
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if (nums[mid] < target && target <= nums[n - 1]) {
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left = mid + 1;
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} else {
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right = mid;
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}
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}
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}
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return -1;
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return nums[left] == target ? left : -1;
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}
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}
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```
@@ -115,23 +133,56 @@ class Solution {
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class Solution {
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public:
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int search(vector<int>& nums, int target) {
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int l = 0, r = nums.size() - 1;
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while (l <= r) {
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int mid = (l + r) >> 1;
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if (nums[mid] == target) return mid;
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if (nums[mid] > target) {
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if (nums[mid] >= nums[r] && target < nums[l]) l = mid + 1;
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else r = mid - 1;
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} else {
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if (nums[mid] <= nums[l] && target > nums[r]) r = mid - 1;
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else l = mid + 1;
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int n = nums.size();
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int left = 0, right = n - 1;
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while (left < right)
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{
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int mid = (left + right) >> 1;
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if (nums[0] <= nums[mid])
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{
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if (nums[0] <= target && target <= nums[mid]) right = mid;
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else left = mid + 1;
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}
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else
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{
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if (nums[mid] < target && target <= nums[n - 1]) left = mid + 1;
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else right = mid;
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}
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}
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return -1;
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return nums[left] == target ? left : -1;
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}
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};
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```
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### **Go**
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```go
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func search(nums []int, target int) int {
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n := len(nums)
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left, right := 0, n-1
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for left < right {
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mid := (left + right) >> 1
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if nums[0] <= nums[mid] {
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if nums[0] <= target && target <= nums[mid] {
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right = mid
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} else {
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left = mid + 1
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}
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} else {
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if nums[mid] < target && target <= nums[n-1] {
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left = mid + 1
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} else {
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right = mid
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}
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}
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}
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if nums[left] == target {
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return left
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}
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return -1
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}
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```
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### **JavaScript**
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```js
@@ -141,29 +192,26 @@ public:
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* @return {number}
142193
*/
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var search = function (nums, target) {
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let l = 0,
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r = nums.length - 1;
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if (l > r) return -1;
147-
while (l <= r) {
148-
let mid = l + Math.floor((r - l) / 2);
149-
if (nums[mid] === target) return mid;
150-
else if (
151-
nums[mid] <= nums[r] &&
152-
target <= nums[r] &&
153-
target >= nums[mid]
154-
)
155-
l = mid + 1;
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else if (
157-
nums[mid] >= nums[l] &&
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target <= nums[mid] &&
159-
target >= nums[l]
160-
)
161-
r = mid - 1;
162-
else if (nums[mid] >= nums[r]) l = mid + 1;
163-
else if (nums[mid] <= nums[l]) r = mid - 1;
164-
else return -1;
195+
const n = nums.length;
196+
let left = 0,
197+
right = n - 1;
198+
while (left < right) {
199+
const mid = (left + right) >> 1;
200+
if (nums[0] <= nums[mid]) {
201+
if (nums[0] <= target && target <= nums[mid]) {
202+
right = mid;
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} else {
204+
left = mid + 1;
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}
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} else {
207+
if (nums[mid] < target && target <= nums[n - 1]) {
208+
left = mid + 1;
209+
} else {
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right = mid;
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}
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}
165213
}
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return -1;
214+
return nums[left] == target ? left : -1;
167215
};
168216
```
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@@ -199,6 +247,33 @@ impl Solution {
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}
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```
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### **TypeScript**
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```ts
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function search(nums: number[], target: number): number {
254+
const n = nums.length;
255+
let left = 0,
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right = n - 1;
257+
while (left < right) {
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const mid = (left + right) >> 1;
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if (nums[0] <= nums[mid]) {
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if (nums[0] <= target && target <= nums[mid]) {
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right = mid;
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} else {
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left = mid + 1;
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}
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} else {
266+
if (nums[mid] < target && target <= nums[n - 1]) {
267+
left = mid + 1;
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} else {
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right = mid;
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}
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}
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}
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return nums[left] == target ? left : -1;
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}
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```
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### **...**
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```

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