How to trace by hand

Given the spj table and the stored procedure$$ below what is the output for

SET @p$0=\text{'}$s$2\text{'}$; CALL $`$proc$`($@p$0,$ @p$1)$; SELECT @p$1$ AS$`$y$\text{'}$

snumberpnumberjnumberqty Edit Copy Deletes$2$p$1$j$2120$ Edit Copy Deletes$2$p$2$j$1200$ Edit Copy Deletes$2$p$2$j$2200$ Edit Copy Deletes$2$p$3$j$1200$ Edit Copy Deletes$3$p$2$j$1600$ Edit Copy Deletes$6$p$3$j$20$

DROP PROCEDURE $`$proc;

CREATE DEFINER$=`$root$`$@$`$localhost$`$ PROCEDURE $`$proc$`($IN $`$x$`$ VARCHAR$(3),$ OUT $`$y$`$ INT$)$ NOT DETERMINISTIC NO SQL SQL SECURITY DEFINER

BEGIN

$$ DECLARE A$\_$SNUMBER VARCHAR$(3)$;

$$ DECLARE FOUND BOOLEAN DEFAULT TRUE;

$$ DECLARE CURSOR$\_$SUPPLIER$\_$NUMBER CURSOR FOR

$$ SELECT snumber

$$ FROM spj

$$ WHERE snumber $=$ x;

$$

$$ DECLARE CONTINUE HANDLER FOR NOT FOUND

$$ SET FOUND $=$ FALSE;

$$ SET y $=0$;

$$ OPEN CURSOR$\_$SUPPLIER$\_$NUMBER;

$$ FETCH CURSOR$\_$SUPPLIER$\_$NUMBER INTO A$\_$SNUMBER;

$$ WHILE FOUND DO

$$ SET y$=$ y$+1$;

$$ FETCH CURSOR$\_$SUPPLIER$\_$NUMBER INTO A$\_$SNUMBER;

$$ END WHILE;

$$ CLOSE CURSOR$\_$SUPPLIER$\_$NUMBER;

END