Search in Rotated Sorted Array

Author: tanjiasheng

Search in Rotated Sorted Array/index.js

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+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+var search = function(nums, target) {
+    const len = nums.length;
+    let low = 0;
+    let high = len - 1;
+    
+    // 边缘情况
+    if (nums.length === 1) return nums[0] === target ? 0 : -1;
+
+    while (low < high) {
+        let mid = parseInt((low + high) / 2);
+        if (nums[mid] === target) return mid;
+        if (nums[high] === target) return high;
+        if (nums[low] === target) return low;
+        if (nums[mid] > nums[low]) {
+            // 左边升序
+            if (nums[low] < target && target < nums[mid]) {
+                high = mid;
+            } else {
+                low = mid + 1;
+            }
+        } else {
+            // 右边升序
+            if (nums[mid] < target && target < nums[high]) {
+                low = mid + 1;
+            } else {
+                high = mid;
+            }
+        }
+    }
+    return -1;
+};

Search in Rotated Sorted Array/readme.md

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+如果mid的值大于low，则代表左边是升序，否则右边升序，如果目标已经在升序序列中，直接对该序列进行常规二分法查找，否则继续查找直到查找到升序序列