leetcode 35 -- Search Insert Position

Search Insert Position

题目：
Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.
You may assume no duplicates in the array.
Here are few examples.
[1,3,5,6], 5 → 2
[1,3,5,6], 2 → 1
[1,3,5,6], 7 → 4
[1,3,5,6], 0 → 0

题意：
给予一个排序的数组和一个目标target，如果找到target返回下标即可，如果没有找到返回该target该插入的位置。

思路：
正常的二分法，找到返回index，如果没找到返回r下标ight+1就行。

代码：

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