Find Peak Element

Java

class Solution {
    public int findPeakElement(int[] nums) {
        int l = 0;
        int r = nums.length - 1;
        while(l + 1 < r){
            int mid = (l+r) / 2;
            if(nums[mid] > nums[mid-1]){
                l = mid;
            }else{
                r = mid;
            }
        }
        return nums[l] > nums[r] ? l:r;
    }
}

Python

def findPeakElement2(self, nums):
    l, r = 0, len(nums)-1
    while l < r:
        mid = l + (r-l)//2
        if nums[mid] > nums[mid+1]:
            r = mid
        else:
            l = mid + 1
    return l