2.1.4 Search in Rotated Sorted Array II

Link: https://oj.leetcode.com/problems/search-in-rotated-sorted-array-ii/

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

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

Write a function to determine if a given target is in the array.

Time: O(n) //because of linear search due to duplicates. Space: O(1)

public class Solution {
    public boolean search(int[] A, int target) {
        int l = 0;
        int r = A.length - 1;
        while(l <= r){
            int m = (l+r)/2;
            if(A[m] == target) return true;
            else if(A[m] > A[l]){
                 //should add to A[l] <= target, not target < A[m] because if target == A[m], we should not decrease high
                if(A[l] <= target && target < A[m]){
                    r = m - 1;
                }
                else{
                    l = m + 1;
                }
            }
            else if (A[m] < A[l]){
                if(A[m] < target && target <=A[r]){
                    l = m + 1;
                }
                else{
                    r = m - 1;
                }
            }
            else{//A[m] == A[l]
                l++;
            }
        }
        return false;
    }
}

Note: 11.3.2014

一遍沒過。記得判斷A[m] 和A[l]的大小。

while(l<=r), not l < r. e.g. When A = {1}, target = 1, if while(l <r) then we will return false. 

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