Flip coin till 3 heads or 3 tails in a row - help with my code?

Question

Hi guys - I wrote this code (named "3heads" in Code Playground) where the computer should flip a coin consecutively till they get 3 of the same results in a row. Technically it runs, but I don't think it runs right because my "while" loop is wrong. Everytime, I get results in less than 5 flips, so what am I doing incorrectly?

Code is named "3heads" in the playground - I don't know how to link it directly here.

Thanks!

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#run program till you get 3 heads or 3 tails in a row consecutively
import random

sides = ["heads", "tails"]

i = 0
while i<10:
flip1 = random.choice(sides)
flip2 = random.choice(sides)
flip3 = random.choice(sides)
if flip1 != flip2 and flip2 != flip3:
print(flip1, flip2, flip3)
i += i
elif flip1 == flip2 and flip2 == flip3:
print(flip1, flip2, flip3)
break

Answer 1

Try this:
import random
sides = ['heads', 'tails']
i = 0
while True:
flip1 = random.choice(sides)
flip2 = random.choice(sides)
flip3 = random.choice(sides)
i += 1
print(flip1, flip2, flip3)
if flip1 == flip2 == flip3:
break
print('After', i, 'tries')

Answer 2

https://code.sololearn.com/cgPCZr7Imhqe/?ref=app

Answer 3

True. I thought we were looking for triplets being the same. As a matter of fact, looping until three in a row are the same is not much harder...

Answer 4

@kuba: I was looking for triplets being the same. But now, I'm gonna try to solve 3 in a row.

Answer 5

@Kuba: this will not detect 3 in a row in:

heads
tails
tails
tails
heads
heads

Answer 6

Hey! Cool idea for the project—you're close, but the issue is that your current code flips three coins at once every time, rather than flipping one at a time and checking for three in a row. That’s why you often get results in fewer flips—it’s not simulating real consecutive coin flips.

Instead, try flipping one coin at a time inside the loop and tracking how many times the same result appears in a row. Here’s a quick example of how you could structure it:

import random

sides = ["heads", "tails"]
count = 0
last_flip = None
total_flips = 0

while count < 3:
flip = random.choice(sides)
print(flip)
total_flips += 1
if flip == last_flip:
count += 1
else:
count = 1
last_flip = flip

print("It took", total_flips, "flips to get 3 in a row!")

This version flips until it gets three of the same in a row. Hope that helps—and if you're ever unsure, you can always flip a coin visit here: https://flipacoinonline.com/ to test randomness outside the code 😄

Let me know if you want help linking your Code Playground file too!