LeetCode刷题之Search Insert Positio

Problem

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

My Solution

class Solution {
    public int searchInsert(int[] nums, int target) {
        int i = nums.length - 1;
        while (i != 0) {
            if (nums[i] == target) {
                return i;
            } else if (nums[i] < target) {
                return i+1;
            }
            i--;
        }
        if (nums[0] >= target) {
            return 0;
        } else {
            return 1;
        }
    }
}

Great Solution

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