LeetCode-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.

public class Solution {
public boolean search(int[] arr, int target) {
    if(arr.length==1&&arr[0]==target){
            return true;
        }
        int left=0;int right=arr.length-1;
        int mid=0;
        while(left<=right){
            mid=(left+right)/2;
            if(target==arr[mid]||target==arr[left]||target==arr[right]){
                return true;
            }
            if(arr[left]<arr[right]){ //正常序列
                if(target<arr[left]||target>arr[right]){
                    return false;
                }
                if(target<arr[mid]){
                    right=mid-1;
                }else{
                    left=mid+1;
                }
            }else if(arr[left]>arr[right]){ //旋转序列
                if(arr[mid]>=arr[left]){
                    if(arr[mid]>target){
                        if(target>arr[left]){
                            right=mid-1;
                        }else{
                            left=mid+1;
                        }
                         
                    }else{
                        left=mid+1;
                    }
                }else{
                    if(arr[mid]>target){
                        right=mid-1;
                    }else{
                        if(arr[left]>target){
                            left=mid+1;
                        }else{
                            right=mid-1;
                        }
                    }
                }
            }else{ //左右一样大
                for(int i=left;i<right;i++){
                    if(arr[i]==target){
                        return  true;
                    }
                }
                return false;
            }
        }
        return false;
    }
}

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转载自blog.csdn.net/weixin_42146769/article/details/89047016