【LeetCode】【Python】162.Find Peak Element
Question
A peak element is an element that is greater than its neighbors.
Given an input array nums, where nums[i] ≠ nums[i+1], find a peak element and return its index.
The array may contain multiple peaks, in that case return the index to any one of the peaks is fine.
You may imagine that nums[-1] = nums[n] = -∞.
Example 1:
Input: nums = [1,2,3,1]
Output: 2
Explanation: 3 is a peak element and your function should return the index number 2.
Example 2:
Input: nums = [1,2,1,3,5,6,4]
Output: 1 or 5
Explanation: Your function can return either index number 1 where the peak element is 2,
or index number 5 where the peak element is 6.
Note:
Your solution should be in logarithmic complexity.
Solution
class Solution(object):
def findPeakElement(self, nums):
""" :type nums: List[int] :rtype: int """
#注意考虑长度为1的情况,不处理下面的代码会出现下标越界的情况
if(len(nums)==1):
return 0
for i in range(len(nums)):
if(i==0):
if(nums[i]>nums[i+1]):
break
elif(i == len(nums)-1):
if(nums[i]>nums[i-1]):
break
else:
if(nums[i]>nums[i+1] and nums[i]>nums[i-1]):
break
return i
简单题,不解释