merge2.pas

关于课件 好多种结构的算法 等等 大家自己看吧

program merg2(input,output,merge1,merge2,merge{,f,g,h});
{eg of 10-7 p219}
Type
  fltype=file of integer;
var
  a,b:integer ;
  f,g,h:fltype;
  flag:boolean;
Procedure scan(var f:fltype);
 var
   x:integer;
 begin 
   while not eof(f) do
    begin
     read(f,x);
     write(x:6);
    end;
 end ;
begin
 assign(f,'merge21');
 assign(g,'merge22');
 assign(h,'merge2');
 reset(f);
 reset(g);
 rewrite(h);
  if not eof(f) then   read(f,a);
  if not eof(f) then   read(g,b);
  flag:=true;
  While flag do
   begin
     if a < b then
      begin
       write(h,a) ;
       if not eof(f) then read(f,a) else flag:=false;
      end
      else
         begin
          write(h,b) ;
          if not eof(g) then read(g,b) else flag:=false;
         end ;
   end;
  if a<=b then write(h,b) else write(h,a);
  While not eof(f) do
      begin
       read(f,a);
       write(h,a) ;
      end ;
  While not eof(g) do
        begin
         read(g,b);
         write(h,b) ;
        end ;
  writeln;
  write('f:');
  reset(f);
  scan(f);
    writeln;
  write('g:');
  reset(g);
  scan(g);
    writeln;
  writeln('f+g:');
  reset(h);
  scan(h);
  close(f);
  close(g);
  close(h);
end.