35. Search Insert Position

class Solution {
    public int searchInsert(int[] nums, int target) {
      int low = 0;
      int high = nums.length - 1;
      while( low <= high){
        int mid = low + (high - low) / 2;
        if(nums[mid] == target){
          return mid;
        }else{
          if(nums[mid] < target){
            low = mid + 1;
          }else{
            high = mid - 1;
          }
        }
      }
      return low;  
    }
}

 

 

Index of the target or 

index of Smallest larger than the target 

class Solution {
    public int searchInsert(int[] nums, int target) {
        // sanity check 
        if(nums == null || nums.length == 0) return 0;
        if(target < nums[0]) return 0;
        if(target > nums[nums.length - 1]) return nums.length;
        int left = 0;
        int right = nums.length - 1;
        
        while(left < right){
            int mid = left + (right - left) / 2;
            if(nums[mid] == target){
                return mid;
            }else if(nums[mid] < target){
                left = mid + 1;
            }else{
                right = mid;
            }
        }
        return left;
    }
}

下面这几个例子都要考虑到才行， 面试的时候也是一样， 自己把这些情况都要考虑到， 面试的时候很可能不给你这么多的例子， 

面试官可能指望你自己考虑周全， 把所有或者大部分的corner case ， edge case 都想到

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