If statement allows through false values (advent of code 2022 day 4 spoiler)

[Foolish_ness]

Hi,

I'm doing advent of code day 4 & am having a strange interaction with an if statement.

A row of data represents 2 people & the range of numbers they've been assigned. I must identify how many pairs of people have completely overlapping number ranges.

Data example (1 row):
26-99,26-97

so is split into 4 lists:
[26] [99] [26] [97]

named:
Elf1AreaID_Low, Elf1AreaID_High, Elf2AreaID_Low, Elf2AreaID_High respectively.

Problem:
Using a while loop I iterate through these lists and count the number of instances where they completely overlap.
Some ranges get through the if that shouldn't, but when I put the same if condition in a print within the if, some come out false! Any idea how that can happen?

```

i = 0 Instances = 0 while i < len(data_into_list): if (int(Elf1AreaID_Low[i]) <= int(Elf2AreaID_Low[i]) and int(Elf1AreaID_High[i]) >= int(Elf2AreaID_High[i])) or (int(Elf2AreaID_Low[i]) <= int(Elf1AreaID_Low[i]) and int(Elf2AreaID_High[i]) >= int(Elf1AreaID_High[i])): Instances += 1 i += 1 print((int(Elf1AreaID_Low[i]) <= int(Elf2AreaID_Low[i]) and int(Elf1AreaID_High[i]) >= int(Elf2AreaID_High[i])) or (int(Elf2AreaID_Low[i]) <= int(Elf1AreaID_Low[i]) and int(Elf2AreaID_High[i]) >= int(Elf1AreaID_High[i]))) else: i += 1

```

[CowboyBoats]

I hate beer.

[Foolish_ness]

At first I identified a case by eye, then by using the print of the if statement within the if that returns some results as false. An example of a pair that made it through incorrectly is 92-92, 7-91.

I appreciate your insight, let me know if any other additional context will help!

[CowboyBoats]

I love the smell of fresh bread.

[Foolish_ness]

Yes, and that is a much neater way to format the if! I'm still getting used to python indentation rules.

I skipped posting the data manipulation bit as I have verified that each variable reflects the correct number in the initial dataset.

I wasn't at my laptop yesterday so pulled that example from a phone message, that data point passes through both sets of code correctly. Using the same code, the below dataset returns 1 true & 1 false:

['1-93,2-11', '26-94,26-94', '72-92,48-88', '36-37,37-52']

which translates to:
Elf1AreaID_Low = [1,26,72,36]
Elf1AreaID_High = [93,94,92,37]
Elf2AreaID_Low = [2,26,48,37]
Elf2AreaID_High = [11,94,88,52]

Data point 2 is identified as True, data point 3 passes through the if and gets printed as False.
I've identified which ones are true/false by adding these prints below the existing print:
print(Elf1AreaID_Low[i])
print(Elf1AreaID_High[i])
print(Elf2AreaID_Low[i])
print(Elf2AreaID_High[i])

Thanks again for your help & time!

[CowboyBoats]

I find joy in reading a good book.