Search Insert Position

最后要checktarget在start之前，在start和end之间和在end之后

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.

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 4:

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

class Solution {
    public int searchInsert(int[] nums, int target) {
        if(nums == null || nums.length == 0)
            return -1;

        int start = 0, end = nums.length -1;

        while(start + 1 < end){
            int mid = start + (end - start) /2;

            if(nums[mid] == target){
                return mid;
            }

            if(nums[mid] < target){
                start = mid;
            }else{
                end = mid;
            }
        }

        if(target <= nums[start]){
            return start;
        }
        else if(target <= nums[end]){
            return end;
        }
        else if(target > nums[end])
            return end+1;
        
        return -1;
       
            
    }
}