out7.txt

pl0的几个小程序 老师给的 很简单 共享下

input file name(PL/0 program file)?   test7.pl0
list object code  ?n
   0 var  a;
   1 procedure  p1;
   1  var  a;
   2  procedure  p2;
   2    var  a;
   3     procedure  p3;
   3      var  a,m;
   4      begin  
   5        a:=4;     write(2*a);  
  12        read(m);  if m#0 then  call  p1
  19      end;
  20   begin  a:=3;
  23     write(2*a);  call  p3
  29   end;
  30  begin  
  31   a:=2;  write(2*a);  call  p2
  39  end;
  40 begin
  41   a:=1;  write(2*a); call  p1
  49 end.
start pl0
       2

       4

       6

       8

?5
       4

       6

       8

?88
       4

       6

       8

?0