insert.pas

来自「关于课件 好多种结构的算法 等等 大家自己看吧」· PAS 代码 · 共 72 行

program insert(input,output,g);
type
 instp=integer ;
 fltp=file of instp;
var
 i,k:integer ; 
 m:instp ; 
 g:fltp ;
 data:string ; 
Procedure inst(var f:fltp ; m:instp);
 var
   i:integer;
   h:fltp;
   x:instp;
 begin
    assign(h,'temp') ;
    rewrite(h);
    x:=m-100;
    while (x<m) and not eof(f) do
     begin
      write(h,x);
      read(f,x);
     end;
    if x<m then  {   eof(f)=true   }
     begin
      write(h,x);
      write(h,m);
     end
    else  {   x>=m  }
     begin
      write(h,m);
      write(h,x);
     end;
    while not eof(f) do
     begin
      read(f,x);
      write(h,x);
     end;
    seek(h,1);
    rewrite(f);
    while not eof(h) do
     begin
      read(h,x);
      write(f,x);
     end ;
    close(f);
    close(h);
 end;
Procedure scan(var f:fltp);
 var
   x:integer;
 begin
   while not eof(f) do
    begin
     read(f,x);
     write(x:5);
    end;
    writeln;
 end ;
begin
 data:='insfile';
 assign(g,data) ;
 reset(g) ; 
 scan(g);
 readln(m);
 reset(g);
 inst(g,m);
 reset(g);
 scan(g);
 close(g);
end.