[leetcode]Binary Search-35. Search Insert Position

Posted 2020-10-20 chenhan05

iven 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.

Example 1:

Input: [1,3,5,6], 5
Output: 2

 

Example 2:

Input: [1,3,5,6], 2
Output: 1

 

Example 3:

Input: [1,3,5,6], 7
Output: 4

 

Example 1:

Input: [1,3,5,6], 0
Output: 0

class Solution {  
public:  
    int searchInsert(vector<int> &nums, int target) {  
        if(nums.size() < 1) {  
            return 0;  
        } else if(nums.size() == 1) {  
            if(nums[0] > target) return 0;  
            else if(nums[0] == target) return 0;  
            else return 1;  
        } else {  
            int flag = 0;     
            if (nums[0] > target) return 0;  
            if(nums[nums.size() - 1] < target) return nums.size();  
            for(int i = 0; i <= nums.size() - 1; ++ i) {  
                if(nums[i] == target) return i;  
                else if (nums[i] < target) flag = i;  
                else {  
                    if(flag == i - 1) return i;  
                }  
            }  
        }  
    }  
};