Answer to Question #50999 in Python for Will

Question

Given a positive integer n , assign True to is_prime if n has no factors other than 1 and itself. (Remember, m is a factor of n if m divides n evenly.)

Answer 1

#!/usr/bin/python
import math
# Question #50999, Programming, Python
# Given a positive integer n, assign True to is_prime
# if n has no factors other than 1 and itself.
# (Remember, m is a factor of n if m divides n evenly.)
n = input("Enter a number: ")
# The method of checking whether a number is prime or not.
# Divide n by all numbers from 2 to square_root(n).
# If n is not divisible by neither of those numbers, then n is a prime number
# Othervise n is not a prime number
# compute square root of n, remove fractional part to get an integer number
sqrtn = int(math.sqrt(n))
is_prime = True # set initial value for is_prime
for i in range(2,sqrtn+1):
if (n % i) == 0: # check if n is divisible by i
is_prime = False # change value of is_prime
break # exit loop
if is_prime:
print n, "is a prime number"
else:
print n, "is not a prime number"