[leedcode 153] Find Minimum in Rotated Sorted Array

Suppose a sorted array is rotated at some pivot unknown to you beforehand.

(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).

Find the minimum element.

You may assume no duplicate exists in the array.

public class Solution {
    public int findMin(int[] nums) {
        //将数组分成两个部分，left不断逼近right，当二者挨着时，right指向的是小的
        //注意：递增数组分开讨论！！
        if(nums==null||nums.length<=0) return -1;
        int left=0;
        int right=nums.length-1;
        if(nums[left]<nums[right])return nums[left];//递增数组
        while(left<right-1){
            int mid=(left+right)/2;
            if(nums[mid]>nums[left]){
                left=mid;
            }else{
                right=mid;
            }
        }
        return nums[right];
    }
}