from math import sqrt
import time
nums = []
s = 0
n = 0
m = 0
lim = 0
yorn = ''

print("Enter a limit for this search: ", end="")
lim = int(input())
if lim == 0:
  lim = 100000000
s = int(sqrt(lim))
tStart = time.time()

nums = [0 for i in range(lim + 1)]

for n in range(2, s):
  if nums[n] == False:
    m = n * n
    while m <= lim:
      nums[m] = True
      m += n

tStop = time.time()
Elapsed = tStop - tStart
print("It took ", (Elapsed % 60), " seconds to complete.")
print("Do you want to list results (Y/N)? ", end="")
yorn = input()

m = 0
for n in range(2, lim):
  if nums[n] == False:
    if yorn == 'y':
      print(n)
    m += 1
print("")
print("Total primes = ", m)