alphabetic phone convert to numeric

[FengG]

I tried really hard on this one, finally came up with this, however, there's space between every number in my result because of the code 'print xxx,' , I want to find a way to delete those spaces.
Program: let user enter say 555-GET-FOOD, convert it to 555-438-3663

alph = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p',\
            'q','r','s','t','u','v','w','x','y','z']
num =[2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,7,8,8,8,9,9,9,9]

phone = raw_input('enter phone number in the format xxx-xxx-xxxx ').lower()

index = 0
for index in range(len(phone)):
    if phone[index].isalpha():
        print num[alph.index(phone[index])],
    else:
        print phone[index],

this is a very intro python course, I did some reasearch online, people using dictionary and enu something or join that we never covered in class. besides the code I used in my program, I was trying to use 'replace', but failed.
It took me hours to came up with the code I already have but I want to make it perfect without the spaces, so any help will be appreciated.

[Gribouillis]

There are many ways to do this. One of them is to append your characters to a list instead of printing them directly. Then you join the list items with an empty string and you print the result.

alph = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p',\
            'q','r','s','t','u','v','w','x','y','z']
num =[2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,7,8,8,8,9,9,9,9]

phone = raw_input('enter phone number in the format xxx-xxx-xxxx ').lower()

accumulator = []
index = 0
for index in range(len(phone)):
    if phone[index].isalpha():
        accumulator.append(num[alph.index(phone[index])])
    else:
        accumulator.append(phone[index])
print ''.join(accumulator)

[FengG]

Thank you very much Gribouillis, but is there any way to do this without the join method? We haven't covered that in class yet.

[sneekula]

The best way for your level would be to build up a string in the loop:

alph = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p',\
            'q','r','s','t','u','v','w','x','y','z']
num =[2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,7,8,8,8,9,9,9,9]

# testing only 
phone = "555-GET-FOOD".lower()
#phone = raw_input('enter phone number in the format xxx-xxx-xxxx ').lower()

# build up from an empty string
s = ""
for index in range(len(phone)):
    if phone[index].isalpha():
        s = s + str(num[alph.index(phone[index])])
    else:
        s = s + phone[index]

print s  # 555-438-3663

[Gribouillis]

Sneekula's way is probably the simplest if you don't want to use 'join'. If you were working with python 3.0 (which is obviously not the case), you could write

L = ['a', 'b', 'c', 'd', 'e']
for x in L:
    print(x, end= '')
print()

which would print abcde.
Before 3.0, the equivalent is

import sys
L = ['a', 'b', 'c', 'd', 'e']
for x in L:
    sys.stdout.write(x)
print

[FengG]

Thank you so much sneekula, this is exactly what I want this to be. I was wondering how I should build a string, because string is immutable. Now im clear. Thank you

[FengG]

Thanks Gribouillis. I am also trying the join method, just for me to learn. It's good