Explain output in C code 😐

Question

Check these two codes, they do the same thing. One is written in C and other one in Java.
Output is different!
I understand output in Java, n=42 then incremented by 1, so n=43 then we check is it equal or less than 43, and we had n++ so n=44. Right?
C ... hmmm, well I guess n is replaced by 42 in if statement and we have 43 <= 42 . 😐

Need an explanation for these two outputs

https://code.sololearn.com/cMSR6c6x2k5y/?ref=app

https://code.sololearn.com/cjBN76ozE71G/?ref=app

Answer 1

i guess its the case of C/C++ undefined behavior
when doing pre and post increment at one statement we dont know which operation is done first.

Answer 2

It starts from the left side. In the such function ++42<=42++ the answer of this operation is 44<=42. C have always have undefined way but this what it does