class Solution {
    public boolean validMountainArray(int[] arr) {
        if (arr.length <= 2) {
            return false;
        }
        int leftSideCounter = 0;
        int rightSideCounter = 0;
        int pointer = 0;
        //left side count
        while (pointer <= arr.length - 2 && arr[pointer] < arr[pointer + 1]) {
            ++leftSideCounter;
            ++pointer;
        }
        //right side counter
        while (pointer <= arr.length - 2 && arr[pointer] > arr[pointer + 1]) {
            ++rightSideCounter;
            ++pointer;
        }
        if (leftSideCounter < 1 || rightSideCounter < 1) {
            return false;
        }
        return leftSideCounter + rightSideCounter + 1 == arr.length;
    }
}