leetcode

0 class Solution {

1 public:

2 bool validMountainArray(vector<int> &arr) {

3 int i = 0;

4 while (i < arr.size() - 1 && arr[i] < arr[i + 1])

5 i++;

6

7 if (i == 0) return false;

8

9 int j = i;

10 while (i < arr.size() - 1 && arr[i] > arr[i + 1])

11 i++;

12

13 if (i == j) return false;

14

15 return i == arr.size() - 1;

16 }

17 };