# This program builds a phone book where the user can
# type a name and look up that person's phone number.
# This version uses a list, which is a poor choice.

def main():
    # build phone book as list
    phonelist = []
    with open("phonenumbers.txt") as file:
        for line in file:
            name, phone = line.split()
            phonelist.append(name)
            phonelist.append(phone)
    
    # look up phone number
    name = input("name to look up? ")
    for i in range(len(phonelist)):
        if phonelist[i] == name:
            print(name, "phone number is", phonelist[i + 1])

main()