program Project2;{$APPTYPE CONSOLE}uses
  SysUtils;
procedure sum(x:integer;y:integer);
var
  z:integer;
begin
  z:=x+y;
  writeln('sum= ',z);
end;function judge(x:integer):boolean;
begin
  if x<0 then
    result:=False               //result 是什么意思,为什么没有声明?
  else
    result:=True;
end;var
  a,b:integer;
begin
  a:=-1;
  b:=10;
  sum(a,b);
  if judge(a) then
    writeln(a,'是正数')
  else
    writeln(a,'是负数');
  if judge(b) then
    writeln(b,'是正数')
  else
    writeln(b,'是负数');
  readln;
end.