Question

Whenever I give a number through the command line, let’s say 92, it only takes the 9, completely ignoring the 2. Yet, if I use arg[1] it will use the 2 instead of the 9.
import sys

for arg in sys.argv:
    print arg

print ""    
print "-----"
print ""    

try:
    argNumber = int(arg[0])
except ValueError:
    argNumber = 0
    print "This is wrong"

for i in range(argNumber, 0, -1):
    print i

Also, for some reason I can’t add a print “This is wrong” line to the except ValueError. It gives me an indention error?

Answer 1

The issue is that you are calling int on arg[0]. Now, arg is what’s left over from the initial loop, when you went through all the arguments in sys.argv – it’s the last element from that loop. So, when you slice it with [0], you are in fact getting the first character from the last argument, rather than – as you intended – the first argument.

Your fix is to simply use sys.argv[1] there instead.