package sprint7.tasks

import java.io.BufferedReader
import java.io.InputStreamReader
import java.util.*

const val M = 1_000_000_007

fun main() {

    val buffer = BufferedReader(InputStreamReader(System.`in`))
    val (vertexCount, edgeCount) = buffer.readLine().split(" ").map { it.toInt() }
    val graph = Array(vertexCount + 1) { mutableListOf<Int>() }

    repeat(edgeCount) {
        val (vertex, toVertex) = buffer.readLine().split(" ").map { it.toInt() }

        graph[vertex].add(toVertex)
    }
    val (start, end) = buffer.readLine().split(" ").map { it.toInt() }

    val queue = LinkedList<Int>().apply { push(start) }
    val foundPaths = IntArray(vertexCount + 1) { 0 }.also { it[start] = 1 }

    while (queue.isNotEmpty()) {
        val cur = queue.poll()
        if (cur == end) {
            continue
        }
        graph[cur].forEach {
            if (foundPaths[it] == 0) {
                queue.add(it)
            }
            foundPaths[it] = (foundPaths[it] + foundPaths[cur]) % M
        }
    }
    println(foundPaths[end])
}