#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

#define pb       push_back
#define mp       make_pair
#define all(x)   x.begin(), x.end()
#define fi       first
#define se       second
#define cl       clear
#define sep      ' '
#define endll    '\n'

const int maxn  =  1e6   + 10;
const int maxn5 =  5e5   + 10;
const int maxnt =  1.2e6 + 10;
const int maxn3 =  1e3   + 10;
const ll  mod   =  998244353 ;
const ll  inf   =  2e18;

int cnt[maxn5][30];
ll dp[30][30];

ll pw(ll a, ll b){return (b == 0 ? 1LL : (pw(a * a % mod, b / 2) * (b % 2 == 1 ? a : 1LL))%mod);}
int main()
{
    //cout << setprecision(15);
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);

    int n, m;
    cin >> n >> m;
    ll fac = 1;
    for(int i = 1; i <= n; i++) fac *= i, fac %= mod;
    for(int i = 0; i < n; i++) for(int j = 0; j < m; j++){
        int a;
        cin >> a;
        cnt[j][n - a + 2]++;
    }
    ll ans = 0;
    for(int i = 0; i < m; i++){
        for(int j = 0; j <= n; j++) for(int k = 0; k <= n; k++) dp[j][k] = 0;
        dp[1][cnt[i][1] - 1] = cnt[i][1];
        for(int j = 1; j < n; j++) for(int k = 0; k <= n; k++){
            if(cnt[i][j + 1] > 0) 
                dp[j + 1][k + cnt[i][j + 1] - 1] += dp[j][k] * (cnt[i][j + 1]); dp[j + 1][k + cnt[i][j + 1] - 1] %= mod;
            if(k > 0) 
                dp[j + 1][k + cnt[i][j + 1] - 1] += dp[j][k] * k; dp[j + 1][k + cnt[i][j + 1] - 1] %= mod;
        }
        ans += (mod + fac - dp[n][0]) % mod; ans %= mod;
    }
    cout << (ans * pw(fac, mod - 2)) % mod << endll;
    return 0;
}