program paradox;
var n, i, j, count:integer;
    S: array[1..325] of string;
    A,B,SY: array [1..325] of char;
    nodo : array[1..26] of integer;
    lettere : array[1..26,1..26] of boolean;
    risposta: string;
    ciclo : boolean;
 
begin
    readln(N);
    for i:=1 to  N  do readln(S[i]);
    for i:=1 to N do begin A[i]:=S[i][1]; SY[i]:=S[i][3]; B[i]:=S[i][5];end;
    for i:=1 to 26 do nodo[i]:=0; ciclo:=false; count:=0;
    for i:=1 to N do begin nodo[ord(A[i])-96]:=nodo[ord(A[i])-96]+1; nodo[ord(B[i])-96]:=nodo[ord(B[i])-96]+1; end;
    for i :=1 to 26 do if nodo[i]<>0 then count:=count+1;
    writeln (count);
    if N<=count+1  then ciclo:=false
                  else ciclo:=true;
    if ciclo=true then risposta:=':('
                  else risposta:=':)';
    writeln(risposta);
 end.

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NQphICZndDsgZgpiICZndDsgYwphICZsdDsgZApkICZsdDsgYwpmICZsdDsgYgo=

5
a > f
b > c
a < d
d < c
f < b