divide_print.md

Divide and print

• it was a basic problem.
• only implementation matters in this one.
• below is mine.

implementation

string isFlexible(int n, vector<int> arr) {
  int i = 1;
  while (i < n and arr[i - 1] < arr[i])
    i++;
  int stop_one = i;

  while (i < n and arr[i - 1] == arr[i])
    i++;
  int stop_two = i;

  if (stop_one == stop_two)
    return "NO";
  if (stop_two == n)
    return "YES";

  while (i < n and arr[i - 1] > arr[i])
    i++;

  return (i == n ? "YES" : "NO");
}