Unexpected ininite loop behavior

Unexpected ininite loop behavior - Printable Version

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Unexpected ininite loop behavior - RedSkeleton007 - Jan-27-2019

Hi, I'm trying to code a basic while True loop, but I get an infinite loop whether or not I use the continue statement (after I purposely enter invalid data to test the loop):

#!/usr/bin/env python3

print("Welcome to the Miles Per Gallon Program.")
print()

milesDriven = float(input("Enter miles driven:               "))
gallonsUsed = float(input("Enter the number of gallons used: "))


while True:
    if milesDriven > 0 and gallonsUsed > 0:
        mpg = round((milesDriven / gallonsUsed),2)
        print("Miles Per Soul... uh... Gallon: ",mpg)
        break
    else:
        print("Both entries must be greater than 0. Please Try again.")
        continue

What's wrong?

RE: Unexpected ininite loop behavior - Larz60+ - Jan-27-2019

while True is by default infinite and since your input statements are outside of the loop, you have no way of satisfying the break condition if it isn't true upon entry.
You need to move the inputs to inside of while loop

RE: Unexpected ininite loop behavior - RedSkeleton007 - Jan-27-2019

Thanks for the quick response. It works now:

#!/usr/bin/env python3

print("Welcome to the Miles Per Gallon Program.")
print()

while True:
    milesDriven = float(input("Enter miles driven:               "))
    gallonsUsed = float(input("Enter the number of gallons used: "))
    if milesDriven > 0 and gallonsUsed > 0:
        mpg = round((milesDriven / gallonsUsed),2)
        print("Miles Per Soul... uh... Gallon: ",mpg)
        break
    else:
        print("Both entries must be greater than 0. Please Try again.")
        continue

RE: Unexpected ininite loop behavior - buran - Jan-27-2019

just to add that continue is not necessary in this case

RE: Unexpected ininite loop behavior - aakashjha001 - Jan-27-2019

while (True) is infinite by default.
The value of the 2 variables are outside the loop and if you enter the values less than 0,it goes into an infinite loop