package main

import (
    "fmt"
)

//  all case w/ dup => dic sorting
func main() {
    var cases int
    fmt.Scanf( "%d\n", &cases )

    for cases > 0 {
        var stdNum int
        var pairNum int
        fmt.Scanf( "%d %d\n", &stdNum, &pairNum )
//        fmt.Printf( "sn: %d pn: %d\n", stdNum, pairNum )

        var areFriends [10][10]bool
        var taken [10]bool

        //  init
        for i:=0; i<10; i++ {
            for j:=0; j<10; j++ {
                areFriends[i][j] = false
            }
        }
        for i:=0; i<10; i++ {
            taken[i] = false
        }

        for i:=0; i<pairNum; i++    {
            var std1 int
            var std2 int
            fmt.Scanf( "%d", &std1 )
            fmt.Scanf( "%d", &std2 )
            areFriends[std1][std2] = true
            areFriends[std2][std1] = true
        }

        fmt.Printf( "%d\n", countPairs(taken, areFriends, stdNum) )

        cases--
    }
}

func countPairs( taken [10]bool, areFriends [10][10]bool, stdNum int )int   {
    var firstFree = -1
    for i:=0; i<stdNum; i++ {
        if !taken[i]    {
            firstFree = i
            break
        }
    }
    if firstFree == -1  { return 1 }

    var count = 0
    for i:=firstFree+1; i<stdNum; i++   {
        if !taken[i] && areFriends[firstFree][i]    {
            taken[i] = true
            taken[firstFree] = true
            count += countPairs( taken, areFriends, stdNum )
            taken[i] = false
            taken[firstFree] = false
        }
    }

    return count
}