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#!/usr/bin/python
# Judge whether a interger is a prime.
#isprime.py
import sys
import math
def isPrime(num):
if not isinstance(num, int):
return False
anum = num
if anum < 0:
anum = math.fabs(anum)
if anum == 1:
return False
if anum == 2 or anum == 3:
return True
if math.fmod(anum, 2) == 0:
return False
endN = math.sqrt(anum) + 1
i = 3
ret = True
while i < endN:
if math.fmod(anum, i) == 0:
ret = False
break;
i += 2
return ret
if __name__ == "__main__":
if len(sys.argv) < 2:
print "usage is:"
print "python isprime.py <value1> [< <space>value2>< <space>value3>...]"
numlist = sys.argv[1:]
n = 0
for num in numlist:
try:
n = int(num)
if isPrime(n) :
print num + " is a prime."
else :
print num + " is not a prime."
except ValueError:
print num + " is not a prime."
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