[Leetcode] Find Peak Element

A peak element is an element, which is greater than its neighbors.

Given an input array where num[i] ≠ num[i+1] , the find a peak element and return its index.

The array may be contain multiple peaks, in this case return the index to any one of the peaks is fine.

May imagine 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.

Hide TagsArray Binary SearchAnalysis: Refer to http://www.cnblogs.com/diegodu/p/4589781.html This is to find the local minimum

The problem is to find the local maximum

classSolution { Public:        intFindpeakelement (vector<int>&nums) {               if(nums.size () = =0)                return-1; if(nums.size () = =1)                return 0; if(nums[0] > nums[1])                return 0; intSize =nums.size (); if(Nums[size-1] > Nums[size-2])                 returnSize-1; intLow =1; intHigh = size-2; intmid;  while(Low <High ) {Mid= (low + high)/2; if(Nums[mid] < nums[mid+1]) { low= mid+1; }                   Else if(Nums[mid] < nums[mid-1]) { high= mid-1; }                Else                    returnmid; }            returnLow ; }};

[Leetcode] Find Peak Element