leetcode_162题——Find Peak Element（数组，水题）

Find Peak Element

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Question Solution

A peak element is an element that is greater than its neighbors.

Given an input array where num[i] ≠ num[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 num[-1] = num[n] = -∞.

For example, in array [1, 2, 3, 1], 3 is a peak element and your function should return the index number 2.

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Credits:
Special thanks to @ts for adding this problem and creating all test cases.

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这题如果只求做出来的话比较水，没啥好说的

#include<iostream>
#include<vector>
using namespace std;
int findPeakElement(vector<int>& nums) {
	int len=nums.size();
	if(len==1)
		return 0;
	if(len==2)
		nums[0]>nums[1]?0:1;
	if(nums[0]>nums[1])
		return 0;
	if(nums[len-1]>nums[len-2])
		return len-1;

	for(int i=1;i<len-1;i++)
	{
		if(nums[i]>nums[i-1]&&nums[i]>nums[i+1])
			return i;
	}
}

int main()
{

}