sort2.pas

关于课件 好多种结构的算法 等等 大家自己看吧

program sort2(input,output,g);
{ use file }
TYPE
 book=Record
       xm : string[16];
       sh : integer ;
       sm : string[16];
       dj : real ;
       Sl : integer ;
      END  ;
 bokfl=file of book;
VAR
 st : string; 
 g : bokfl; 
Procedure sort(var f:bokfl);
  var
    i,j,n:integer;
    x,y,temp:book;
  begin 
    n:=filesize(f)-1;
    for i:=0 to n-1 do
      begin
       seek(f,i); 
       read(f,x);   
       for j:=i+1 to n do
        begin
         seek(f,j);  
         read(f,y);        
         if x.sh>y.sh then
           begin 
            seek(f,j); 
            write(f,x);
            seek(f,i);
            write(f,y);
            temp:=x;
            x:=y;
            y:=temp;
           end ;
        end; 
       end; 
  end ;
 Procedure scan(var f:bokfl);
 var
   x:book;
 begin
   while not eof(f) do
    begin
     read(f,x);
     with x do
      begin
        writeln( xm :20,sh:6,sm:20,dj:5:2,Sl:6);
      end;
    end ;
 end;
BEGIN 
  st:='book2';
  assign(g,st);
  reset(g); 
  scan(g);
  reset(g);
  sort(g) ;
  reset(g);
  writeln('after sort:');
  scan(g);
  close(g) 
END.