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Yu-Che Hung
Courses Plus Student 10,607 Pointswhy? should I subtract ?
why? should I subtract one ?
len(arg)-1
# 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
3,332 PointsBecause 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