153. Find Minimum in Rotated Sorted Array - jiejackyzhang/leetcode-note GitHub Wiki

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.

解题思路为Binary Search。

若mid>right，则说明min肯定在mid右边；若mid<=right，则min在mid左边（包括mid）。 当left == right时，此时即为min。

public class Solution {
    public int findMin(int[] nums) {
        int left = 0;
        int right = nums.length - 1;
        while(left < right) {
            int mid = left + (right - left) / 2;
            if(nums[mid] > nums[right]) {
                left = mid + 1;
            } else {
                right = mid;
            }
        }
        return nums[left];
    }
}