leetcode 35 Search Insert Position
z
 2017-12-22 14:00:56

35. Search Insert Position

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:

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

Example 2:

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

Example 3:

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

Example 1:

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

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class Solution {
    public int searchInsert(int[] nums, int target) {
        // 开始时进行特例设置，但是这里可以省去，因为当n==0时，low=0， high=-1,不会进入while循环，返回low=0
      	int n = nums.length;
        if(n == 0){
            return 0;
        }
        int low = 0;
        int high = n-1;
        while (low <= high){
            int mid = (high + low)/2;
            if(nums[mid]< target){
                low = mid+1;
            }
            else if(nums[mid]> target){
                high = mid-1;
            }
            else{
                return mid;
            }
        }
        return low;
    }
}

简单的二分查找。