text: n, m = map(int, input().split())
  arr = list(map(int, input().split()))[:n]
  flag = True
  for i in range(n-1):
      if arr[i+1]-arr[i] > m:
          flag = False
  if flag and ((42195-arr[len(arr)-1]) <= m):
      print("S")
  else:
      print("N")