您的位置:首页 > 其它

154. Find Minimum in Rotated Sorted Array II leetcode binary search

2017-01-04 13:48 447 查看
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 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.
The array may contain duplicates.
注意:该数组中包含重复的元素
int findMin(vector<int>& nums) {
int low = 0;
int high = nums.size() - 1;

while(low < high)
{
if(nums[low] < nums[high])
return nums[low];

//进入到以下部分说明不能满足上述的if条件,即以下部分nums[low] > nums[high]
int mid = low + (high - low) / 2;
if(nums[mid] > nums[low])
low = mid + 1;
else if(nums[mid] < nums[low])
high = mid; //此处没有high = mid + 1 是因为nums[mid] < nums[high],那么mid处有可能是最先的数字
else
low++; //多加了一句,即当nums[mid] == nums[low]的时候,因为数组中有重复的元素,所以不清楚最小的元素出现在哪部分,是出现在low~mid之间还是mid~high之间,所以只将low++
}

return nums[low];
}
内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
标签: