How to find if the given strings can be found inside the second strings

Question

I would like to know how to write a function that returns True if the first string, regardless of position, can be found within the second string by using two strings taken from user input. Also by writing the code, it should not be case sensitive; by using islower() or isupper().

Example Outputs:

1st String: lol

2nd String: Hilol

True

1st String: IDK

2nd String: whatidk

True

My code:

a1 = str(input("first string: "))
a2 = str(input("second string: "))

if a2 in a1: 
    print(True)
else:
    print(False)

It outputs:

1st String: lol

2nd String: lol

True

1st String: lol

2nd String: HIlol

False #This should be true, IDK why it is false.

I only came this far with my code. Hoping someone could teach me what to do.

How did you arrive at the conclusion that `HIlol` is itself a substring of `lol`? Wouldn’t that be the other way around? — esqew, Nov 18 '22 at 06:55
OH I FOUND OUT THAT MY COULD SHOULD BE OTHER WAY AROUND, NOT a2 in a1, but a1 in a2 — Nemethste, Nov 18 '22 at 06:59
Does this answer your question? [Does Python have a string 'contains' substring method?](https://stackoverflow.com/questions/3437059/does-python-have-a-string-contains-substring-method) — mousetail, Nov 18 '22 at 08:14

Nineteendo · Answer 1 · 2022-11-18T09:12:39.460

1

Is this what you're looking for?

string_1 = input("first string: ")
string_2 = input("second string: ")

if string_1.lower() in string_2.lower(): 
    print(True)
else:
    print(False)

A "function" would be:

def check_occuring(substring, string):
    if substring.lower() in string.lower(): 
        return True
    else:
        return False

string_1 = input("first string: ")
string_2 = input("second string: ")
print(check_occuring(string_1, string_2))

Please note that you can also just print or return substring.lower() in string.lower()

edited Nov 18 '22 at 09:12

answered Nov 18 '22 at 07:02

Nineteendo

882
3
18

1

Why the explicit test? Just: *return substring.lower() in string.lower()* – DarkKnight Nov 18 '22 at 08:24
@Cobra, it's more readable this way, and this way the code is more in line with the original code of the user. – Nineteendo Nov 18 '22 at 09:11

score 0 · Answer 2 · answered Nov 18 '22 at 07:03

If you want the Program to be case sensitive, just make everything lowercase

substring = input("substring: ").lower()
text = input("text: ").lower()

To check if a substring can be found in another string can be done by using the keyword in

>>> "lol" in "HIlol"
True

maybe check your inputs here. The whole program would be

substring = input("substring: ").lower()
text = input("text: ").lower()

print(substring in text)

note: <str> in <str> gives you a boolean so you can use it in if conditions. In this case you can just print the boolean directly.

How to find if the given strings can be found inside the second strings

2 Answers2