[leetcode刷题系列]Search in Rotated Sorted Array II

来源：互联网发布：php商城分销系统源码编辑：程序博客网时间：2024/04/30 08:46

- - 这题反正我是没想到确定性的logn的算法。我的解法最坏情况下是O(n)

class Solution {public:    bool search(int A[], int n, int target) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        if(n <= 0)            return false;        if(A[0] == target || A[n - 1] == target)            return true;        while(n > 1)            if(A[n - 1] == A[n - 2])                -- n;            else                break;        if(A[n - 1] == A[0])            --n;        if(n <= 0)            return false;        int low = 0, high = n - 1, mid;        while(low <= high)            if(A[mid = low + high >> 1] < A[0]) high = mid - 1; else low = mid + 1;        int p = low;        // left        low = 0, high = p - 1;        while(low <= high)            if(A[mid = low + high >> 1] >= target) high = mid - 1;else low = mid + 1;        if(low >= 0 && low < n && A[low] == target)            return true;        low = p, high = n - 1;        while(low <= high)            if(A[mid = low + high >> 1] >= target) high = mid - 1;else low = mid + 1;        if(low >= 0 && low < n && A[low] == target)            return true;        return false;    }};