#数组 #二分查找 #leetcode

binary_search_704.cpp

class Solution {
public:
    int search(vector<int>& nums, int target) {
        if (nums[0] > target || nums.back() < target)
            return -1;

        int left = 0, right = nums.size() - 1;
        // [left, right]
        while (left <= right) {
            int mid = left + (right - left) / 2;
            if (target < nums[mid]) {
                right = mid - 1; // [left, mid-1]
            } else if (target > nums[mid]) {
                left = mid + 1; // [mid+1, right]
            } else if (target == nums[mid]) {
                return mid;
            }
        }
        return -1;
    }
};