# coding: utf-8

import re
from scipy import integrate
from operator import itemgetter
from collections import defaultdict as dd
from collections import Counter
from collections import deque
from collections import namedtuple
import numpy as np
import fractions
import itertools
import math
from copy import deepcopy as dcopy
import heapq
from math import cos, sin, radians

def main():
    global mapping
    N, M = map(int, input().split())

    mapping = [[False]*N for n in range(N)]
    for m in range(M):
        a, b = map(int, input().split())
        mapping[a][b] = True
        mapping[b][a] = True

    # print(mapping)

    count = 0
    for c in itertools.combinations(range(N), 4):
        if check(c):
            print(c)
            count += 1

    print(count)

def check(p):
    stack = [(p[0], 1)]
    count = 0
    while len(stack) != 0:
        now, num = stack.pop()
        for i in range(4):
            if connected(now, p[i]):
                if num + 1 == 4:
                    count += 1
                else:
                    stack.append((p[i], num + 1))
    if count == 1:
        return True
    else:
        return False


def connected(x,y):
    if mapping[x][y] or mapping[y][x]:
        return True
    else:
        return False


if __name__ == "__main__":  # {{{
    try:
        import test
        test.test()
    except:
        main()  # }}}