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Python

Posted by Hara Gopal K
Hara Gopal K
Courses Plus Student 10,027 Points

random choices

I managed to do this the following way, but couldn't understand why i had to put the b-1 (why minus) as the condition for the loop. Can someone please help:

  1. a is an iterable
  2. b is an integer
import random

def nchoices (a, b):

    lst = []
    i = 0

    while i <= b-1:
        lst.append (random.choice(a))
        i += 1
    print (lst)

nchoices(['hello', 'prost', 'merci', 'ahoy'], 10)

1 Answer

tobiaskrause
tobiaskrause
9,160 Points
tobiaskrause
tobiaskrause
9,160 Points

Well...every run in this loop i will increment by 1 So the first loop-statement is

  • 0 <= 10 - 1 = true
  • 1 <= 10-1 = true
  • 2 <= 10-1 = true
  • 3 <=10-1 = true
  • 4 <=10-1 = true
  • 6<=10-1 = true
  • 7<=10-1 = true
  • 8<=10-1 = true
  • 9<=10-1 = true
  • 10<=10-1 = FALSE

if you would do i <= b you would print the solution 11 times not 10 times. Because your first value of i = 0. If you would do i = 1 in the beginning would could go i <= b. Also you have to understand, that while i will increment every time, b will not change. b will always be 10 since you dont assign values in statements.

Hara Gopal K
Hara Gopal K
Courses Plus Student 10,027 Points

Thank you very much Tobias :)