The while statement, execution (1)

Syntax:

while CONDITION:
  STATEMENT1
  ...
  STATEMENTn

Example

# program with a while loop
n = 0
while n < 20:
  print n,
  n = n+1

Operation:

  1. evaluate CONDITION, yielding TRUE or FALSE

  2. if CONDITION is FALSE, exit the while statement, and continue the program below the while statement

    if CONDITION is TRUE, execute STATEMENT1,..,STATEMENTn, and go back to step 1