Given the underneath fragment code that is written in C language, Write down the function with domain and codomain then prove that function is injective (One to one) but it's not surjective (Onto)? SHOW ALL YOUR WORKS, a counterexample is NOT ENOUGH, _you have to disprove surjectivity and prove injective.

void fun(unsigned int *m, unsigned int *n ){

( *m=5 * (*m) + (*n);

*n=(*n) (*n);