Difficulty understanding nested loops with addition, range and print function

Question

When I try to put this python code within the input 12, I get the answer is 0, 6, 18. I don't know how to calculate that and I keep visualizing it as code snippet 2, with the answers 0,0,1,3,6,6,8,12.

How does this loop work?

stop=int(input())

result=0

for a in range(5): 

  for b in range(4): 

    result += a * b

  print(result)

  if result > stop: 

    break 

What I calculate

stop=int(input())

result=0

for a in range(5): 

  for b in range(4): 

    result += a * b

    print(result)

  if result > stop: 

    break 

Answer 1

I will walk you through the for in range(5) loop.

First, a = 0, result = 0.

This loops 4 times and result remains at 0 because 0 * b = 0

0 is printed

Next, a = 1, result = 0.

The Result += 1x0 + 1x1 + 1x2 + 1x3

So result = 0 + 6

6 is printed

Finally, a = 2, result = 6.

Result += 2x0 + 2x1 + 2x2 + 2x3

So result = 6 + 12 = 18

18 is printed

if result > stop evaluates to true so your loop is broken.

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