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# 2024
# Maciej Szeptuch

import sys
from heapq import heappush, heappop
from bisect import bisect, insort

MOD = 1000000007


def combine(perm1, perm2):
    return tuple(perm1[b - 1] for b in perm2)


def inversions(perm):
    heap = []
    count = 0

    for i, v in enumerate(perm):
        heappush(heap, (v, i))

    idxs = []
    while heap:
        _, i = heappop(heap)
        y = bisect(idxs, i)
        count = (count + i - y) % MOD
        insort(idxs, i)

    return count


def gcd(a, b):
    if a == 0:
        return b, 0, 1

    g, x, y = gcd(b % a, a)
    return g, y - (b // a) * x, x


if __name__ == "__main__":
    data = [int(x) for x in sys.stdin.read().split()]

    length = data[0]
    permutations = data[1]
    favourite = []
    combined = set()

    for p in range(permutations):
        favourite.append(tuple(data[2 + p * length : 2 + (p + 1) * length]))
        combined.add(favourite[p])

    que = list(combined)
    while que:
        elem = que.pop()
        for permutation in favourite:
            new_perm = combine(elem, permutation)
            if new_perm not in combined:
                combined.add(new_perm)
                que.append(new_perm)

    total_inversions = 0
    for perm in combined:
        total_inversions = (total_inversions + inversions(perm)) % MOD

    print((gcd(len(combined), MOD)[1] * total_inversions) % MOD)