public Boolean isValidMountain(int[] arr){
while(i < arr.Length && i + 1 < arr.Length && arr[i] < arr[i + 1]){
if(i == 0 || i + 1 >= arr.Length){
while(i < arr.Length && i + 1 < arr.Length){
if(arr[i] <= arr[i++ + 1]){
public static void Main()
Boolean result = isValidMountain(arr);
Console.WriteLine("is Valid mountian :" + isValidMountain(arr));