uses crt;

type
  matrix= array[1..5,1..5] of integer;

var
  f:matrix;
  p:integer;

procedure input(var d:matrix;n,k:integer);
var
  i,j:integer;
begin
  clrscr;
  randomize;
  for i:=1 to n do begin
    for j:=1 to k do
      d[i,j]:=random(20);
  end;
end;

procedure output(var d:matrix;n,k:integer);
var
  i,j:integer;
begin
  for i:=1 to n do begin
    for j:=1 to k do
      write(d[i,j]:4);
    writeln;
  end;
end;

function pr(var d:matrix;n,k:integer):integer;
var
  i, j:integer;
  p1:integer;
begin
  p1:=1;
  for j := 1 to (n div 2) + 1 do
    for i := j to n - j + 1 do begin
      p1 := p1 * d[i, j];
      d[i, n - j + 1] := 0;
    end;
  pr:=p1;
end;

begin
  input(f,5,5);
  writeln('matrix f before');
  output(f,5,5);
  p:=pr(f,5,5);

  writeln('matrix f after');
  output(f,5,5);
  writeln(p);
  readln;
end.