154. Find Minimum in Rotated Sorted Array II(剑指offer)

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Follow up for "Find Minimum in Rotated Sorted Array":
What if duplicates are allowed?

Would this affect the run-time complexity? How and why?

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.

The array may contain duplicates.

 

class Solution {
    public int findMin(int[] a) {
           if(a.length==0) return 0 ;
        int left = 0,right = a.length-1,mid=0;
        while(a[left]>=a[right]){
            if(right-left==1) return a[right];
            
            mid = left +(right-left)/2;
           // 特殊处理[1 1 1 0 1]
            // code
            if((a[mid]==a[right])&&(a[mid]==a[left]))
                return find_min(a,left,right);
            //
            if(a[left]<=a[mid]) left =mid;
            if(a[right]>=a[mid])right = mid;
        }
        return a[mid];
    }
    private int find_min(int[] a,int left,int right){
        int min = a[left];
        for(int i =left;i<=right;i++)
            if(a[i]<min) 
                min =a[i];
        return min;
    }
}