Given is the following program

void main $()$

$\{$

int n$,$x$,$yifflag, a;

cin $a\frac{\text{;}}{\frac{?}{?}}$ input a

cin$x$; $//$ input $x$

cin$y\frac{\text{;}}{\frac{?}{?}}$ input $y$

cin$n\frac{\text{;}}{\frac{?}{?}}$ input $n$

$i=3$;

flag $=1$;

C$1$ C$2$

while $(0a++y=a,((a==x)||(a==y)),=2$