Python Forum

Problem: So Hey! Friends I Have Another Challenge And Is From My Friends!
He Challenged Me For The Problem Below But I Failed SO I Decided To Ask Here
So, I Have 2 Lists and i have to loop through each character and get a pair of 2 numbers that add upto 24
Fun Part: He Also Don't Know Answer

Here Is The List1 And List2:

list1 = [-1,3,8,2,9,5]
list2 = [4,1,2,10,5,20]

Do you need to take one element from each list or not? (disregarding the fact that we can spot a solution a mile away)
(or do you mean a pair each of 2 numbers = 4?)
If you don't , add the lists together and loop over them.
If you do, you may need 2 loops.
Paul

(Aug-12-2020, 05:13 PM)DPaul Wrote: [ -> ]Do you need to take one element from each list or not? (disregarding the fact that we can spot a solution a mile away)
If you don't , add the lists together and loop over them.
If you do, you may need 2 loops.
Paul

Ahh, Sorry But I Don't Understand What are you telling

(Aug-12-2020, 05:14 PM)Harshil Wrote: [ -> ]Ahh, Sorry But I Don't Understand What are you telling

Not so fast, i was still typing
Then you can take several routes, one of them is examine combinations of 2.
You will need to import itertools -> combinations.

paul

(Aug-12-2020, 05:22 PM)DPaul Wrote: [ -> ]

(Aug-12-2020, 05:14 PM)Harshil Wrote: [ -> ]Ahh, Sorry But I Don't Understand What are you telling

Not so fast, i was still typing
Then you can take several routes, one of them is examine combinations of 2.
You will need to import itertools -> combinations.

paul

Wait Wait Combos Do You Mean

OK, let's take this one step at the time.
Your post is called "2 pairs, 2 lists".
Are you looking to find a pair in each list that will sum up to 24 ?

If so the algorithm for 1 list, will be the same for the other.

Paul

list1 = [-1,3,8,2,9,5]
list2 = [4,1,2,10,5,20]

for e1, e2 in zip(list1, list2):
    print(e1, e2)

Output:
-1 4
3 1
8 2
2 10
9 5
5 20

Or if you want to make a new list from it:

list12 = list(zip(list1, list2))

If you require other results, then give us an example.

There are only two numbers that add up to 24; 4 + 20, and they are both in the same list. You cannot add a number from list1 to a number from list2 to get 24. If you are just looking for two different numbers and the numbers can be from either list, the answer is 4 and 20

To solve the answer using one number from each list:

for a in list1:
    for b in list2:
        if a + b == 24:
            print(f'{a} + {b} = 24')

Tp solve for any combination of numbers in either list:

numbers = list1 + list2
for a in numbers:
    for b in numbers:
        if a + b == 24:
            print(f'{a} + {b} = 24')

This could be made more efficient if the lists were large or if you wanted to avoid double answers (4, 20 and 20, 4)