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(int n, int *x.int *y){ *x="n-7; 'y=n+3