hackertyper.net
Jelly, 4 bytes
ẋ3ṁ@
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How it works
ẋ3ṁ@ Main link. Arguments: s (input string), t (file string)
ẋ3 Repeat s three times.
ṁ@ Mold; reshape t like the previous result.
This repeats the elements of t over and over until the length matches that
of s repeated thrice.
J, 7 bytes
$~(3*#)
Takes two arguments, the text to be repeated and the user's input text.
Usage
The input text is formatted where ,
means to join and LF
is the newline character.
f =: $~(3*#)
('#include <stdio.h>', LF, 'int main() { }') f 'hello world'
#include <stdio.h>
int main() { }
'hello' f 'hello world'
hellohellohellohellohellohellohel
Try it online. (tryj.tk)
Jelly, 9 bytes
⁴L×3
ẋ¢ḣ¢
Try it online!
⁴L×3 Define nilad as ¢:
L length of
⁴ second argument
×3 tripled
ẋ¢ḣ¢ Main chain:
the first argument (implicit)
ẋ repeated
¢ ¢ many times
ḣ¢ then get the first ¢ characters of it.