$($Assume the user always enters $\text{'}$q$\text{'})$

z $=0$;

c $=\text{'}$y$\text{'}$;

while $($c $=\text{'}$y$\text{'})\{$

printf$("\%$d $",$ z$)$;

scanf$("\%$c$",$ &c$)$;

z $=$ z $+1$;

$\}$