uses crt;
Var k,t,i,j,tong,ton,n:longint; a:array[1..100000]of string;
begin
clrscr;
write('n=');readln(n);
for i:=1 to n do
begin
write('a[',i,']=');readln(a[i]);
end;
write('Cac so hanh phuc: ');
for i:=1 to n do
begin
k:=length(a[i]) div 2;
if (length(a[i]) mod 2=0) then
begin tong:=0; ton:=0;
for j:=1 to k do begin val(a[i][j],t); inc(tong,t); end;
for j:=k+1 to n do begin val(a[i][j],t); inc(ton,t); end;
if tong=ton then write(a[i],' ');
end;
readln
end.