Suppose an array sorted in ascending order 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.
一刷
思路：首先判断序列是不是ascending的。如果不是，然后再判断左half还是右half是ascending的。
public class Solution {
public int findMin(int[] nums) {
if(nums.length == 0) return -1;
int lo = 0, hi = nums.length-1;
while(lo<hi){
if(nums[lo]<nums[hi]) return nums[lo];
int mid = lo + (hi-lo)/2;
if(nums[mid]>=nums[lo]){//left half is sorted
lo = mid+1;
}else{
hi = mid;//should not exclusive the mid
}
}
return nums[lo];
}
}
