过程调用（向下）.txt

PL0语言的编译器

var a;
procedure   p;
	var b;
	procedure  q;
		var c;
		begin
			c:=2;
                                                write(c);
			b:=2+3+4-1+5*6*1+3/2/3+1;
                                                write(b)
		end;
	begin
		call q;		
		read(a)
	end;
begin      
        call p;
        write(a)
end.