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Python Python Basics (2015) Letter Game App Random Item

Yu-Che Hung
PLUS
Yu-Che Hung
Courses Plus Student 10,607 Points

why? should I subtract ?

why? should I subtract one ?

len(arg)-1

item.py
# EXAMPLE
# random_item("Treehouse")
# The randomly selected number is 4.
# The return value would be "h"
# EXAMPLE
# random_item("Treehouse")
# The randomly selected number is 4.
# The return value would be "h"
import random
def random_item(arg):
    random_index = random.randint(0,len(arg)-1)
    return arg[random_index]

1 Answer

Salvador Martinez
Salvador Martinez
3,332 Points

Because when going through a list indexing starts at 0, Example "word" w = 0 o = 1 r = 2 d = 3 But really there is 4 letters so that's why you subtract 1