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Caesar shift cipher
Introduction
What is the Caesar shift cipher (ROT$n$)? It's basically a cipher sequence that changes a letter's value from the number chosen. If we use ROT1 on "games", we get "hbnft". The basic interpretation of the cipher is iterating the value of a letter by 1 $n$ times. If you still don't understand, try using the ROT13 website.
Challenge
Make a program that takes input of a number from 1 to 25, call it $n$, and takes input of a string. It could be any. Then, use $n$ to convert the string into ROT$n$ and output the result.
Examples of inputs and outputs:
If $n = 4$ and string is "Hello, world.", we get Lipps, asvph.
If $n = 15$ and string is "trololol", we get igdadada.
If $n = 7$ and string is "gxoxk zhggt zbox rhn ni", we get never gonna give you up.
If $n = 24$ and string is "I want breakfast!", we get G uylr zpcyidyqr!.
If $n = 13$ and string is "guvf grkg vf fhf", we get this text is sus.
Shortest program wins.
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Python 3, 86 85 bytes
The reasoning behind why this works is basically that 1. we can directly compare the ordinal values of characters (apparently) and 2. we only need that if a character is alphanumeric, then
'A' < '`' < 'a'which is very interesting to think about.
Also, if we have an expression of the form a+(b)<<c or a+b<<c, apparently Python interprets that as (a+b)<<c, which is cool, but so weird.
Solution:
lambda m,k:''.join([c,chr((o:=2+('`'<c)<<5)+(ord(c)+k-o)%26)][c.isalpha()]for c in m)
Try it online! I set the link to Never expire, but please notify me if the link doesn't work.
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