Code Golf: Prime Factors of a Number [closed]

Answer 1

Python (228 chars without I/O, 340 with):

import sys

def primeFactors(n):
    l = []
    while n > 1:
        for i in xrange(2,n+1):
            if n % i == 0:
                l.append(i)
                n = n // i
                break
    return l if len(l) > 0 else [n]

n = int(sys.argv[1])
print '%d: %s' % (n, 'x'.join(map(lambda x: str(x), primeFactors(n))))

Can be compressed to 120 chars:

import sys
n,l=int(sys.argv[1]),[]
while n>1:
 for i in range(2,n+1):
    if n%i==0:l+=[str(i)];n/=i;break
print'x'.join(l)

Note: That's a tab character before the if, not four spaces. It works as another level of indentation and only costs one character instead of two.