The first line contains two integers $n$ and $e$, denoting the number of keys and the size of the alphabet ($1 \le n \le 100$; $2 \le e \le 26$).

The $i$-th of the following $n$ lines consists of characters $L_{i,1}, L_{i,2}, \ldots, L_{i, |L_i|}$, denoting the sequence of letters key $i$ initially contains ($1 \le |L_{i}| \le 10$). Every character is one of the first $e$ lowercase English letters.