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public class Solution {
    public int findPeakElement(int[] nums) {

        int lo = 0;
        int hi = nums.length - 1;

        while (lo < hi) {
            int mid = (lo + hi) / 2;
            if (nums[mid] < nums[mid + 1])
                lo = mid + 1;
            else
                hi = mid;
        }

        return lo;
    }
}