二分查找简单模板

Leetcode35

注意边界条件，时间复杂度O(logn)

class Solution {
public:
    int searchInsert(vector<int>& nums, int target) {
        int left = 0, right = nums.size() - 1; // 注意
        while(left <= right) { 
            int mid = (left + right) / 2; 
            if(nums[mid] == target) { 
                // 相关逻辑
            } else if(nums[mid] < target) {
                left = mid + 1; 
            } else {
                right = mid - 1; 
            }
        }
        // 相关返回值
        return 0;
    }
}