BIBOARD Pascal

var a:array[1..100,1..100]of string;
    q:array[1..10000]of string;
    n,m,k,d:longint;

procedure qs(l,h:longint);
var i,j:longint;
    x,t:string;
begin
    i:=l;j:=h;
    x:=q[(l+h) div 2];
    repeat
        while q[i]<x do inc(i);
        while q[j]>x do dec(j);
        if i<=j then
        begin
            t:=q[i];
            q[i]:=q[j];
            q[j]:=t;

            inc(i);
            dec(j);
        end;


    until i>j;

    if i<h then qs(i,h);
    if j>l then qs(l,j);
end;

procedure nhap;
var i,j,t:longint;
    c:char;
begin
    readln(k,n,m);
    for t:=1 to k do
        for i:=1 to n do
        begin
            for j:=1 to m do
            begin
                read(c);
                a[i,j]:=a[i,j]+c;
            end;
            readln;
        end;
  //  for i:=1 to n do
  //  begin
  //      for j:=1 to m do write(a[i,j],' ');
  //      writeln;
 //   end;
end;

procedure chuyen_1_chieu;
var i,j:longint;
begin
    d:=0;
    for i:=1 to n do
        for j:=1 to m do
        begin
            inc(d);
            q[d]:=a[i,j];
        end;
  //  writeln(d);
end;

procedure giai;
var i,j,s:longint;
begin
    chuyen_1_chieu;

    qs(1,d);
    //   for i:=1 to d do
      //  write(q[i]:8);
    S:=0;
    for i:=2 to d do
        if q[i]<>q[i-1] then inc(s);
    writeln(s+1);
end;

begin
    assign(input,'BIBOARD.inp');reset(input);
    assign(output,'BIBOARD.out');rewrite(output);
    nhap;
    giai;
    close(input);close(output);
end.