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Problem J
Deterministic Finite Automata - Is a Finite Language?

Languages en is

You are given a deterministic finite automaton that accepts the language $\mathcal{L}$. You should output whether $\mathcal{L}$ is a finite language.

Input

The input contains the description of a deterministic finite automaton.

The first line contains four positive integers $n$, $c$, $s$, and $f$, where $n$ is the number of states, $c$ is the size of the alphabet, $s$ is the initial state, and $f$ is the number of final states. The second line consists of a string $\Sigma = \Sigma _1\Sigma _2\dots \Sigma _c$ of $c$ distinct symbols, each of which is a lowercase english character. The third line consists of $f$ distinct positive integers, the set of final states. Then $n$ lines follow, each with $c$ positive integers, describing the symbol table. The $j$-th integer on the $i$-th of those lines represents the state transitioned to from state $i$ upon reading $\Sigma _j$.

Each state is an integer between $1$ and $n$. It is guaranteed that $1 \leq n \leq 10\, 000$, $1 \leq s \leq n$, and $0 \leq f \leq n$.

Output

Output finite if $\mathcal{L}$ is a finite language, otherwise output infinite.

Sample Input 1 Sample Output 1
4 2 2 2
ab
2 4
2 3
3 2
3 3
1 2
infinite
Sample Input 2 Sample Output 2
4 4 1 2
acgt
1 2
2 2 2 2
3 3 3 3
4 4 3 4
3 3 3 4
finite

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