import sys
import math

x_list = []

for line in sys.stdin.readlines():
  x_list.append(int(line.strip()))

count = 0

x_list.remove(x_list[0])

for i in x_list:
  flag = 0
  for j in range(2, int(math.sqrt(i))+1):
    if i % j == 0:
      flag = 1
      break
  if flag == 0:
    count += 1

print count
    