func_code_string: #include <bits/stdc++.h>   using namespace std;      #ifdef LOCAL   #define DEBUG(...) debug(#__VA_ARGS__, __VA_ARGS__)   #else   #define DEBUG(...) 6   #endif      template<typename T, typename S> ostream& operator << (ostream &os, const pair<T, S> &p) {return os <<  (  << p.first <<  ,   << p.second <<  ) ;}   template<typename C, typename T = decay<decltype(*begin(declval<C>()))>, typename enable_if<!is_same<C, string>::value>::type* = nullptr>   ostream& operator << (ostream &os, const C &c) {bool f = true; os <<  [ ; for (const auto &x : c) {if (!f) os <<  ,  ; f = false; os << x;} return os <<  ] ;}   template<typename T> void debug(string s, T x) {cerr << s <<   =   << x <<   n ;}   template<typename T, typename... Args> void debug(string s, T x, Args... args) {for (int i=0, b=0; i<(int)s.size(); i++) if (s[i] ==  (  || s[i] ==  { ) b++; else   if (s[i] ==  )  || s[i] ==  } ) b--; else if (s[i] ==  ,  && b == 0) {cerr << s.substr(0, i) <<   =   << x <<   |  ; debug(s.substr(s.find_first_not_of(   , i + 1)), args...); break;}}      template<int MOD>   struct ModInt {       long long v;       ModInt(long long _v = 0) {v = (-MOD < _v && _v < MOD) ? _v : _v % MOD; if (v < 0) v += MOD;}       ModInt& operator += (const ModInt &other) {v += other.v; if (v >= MOD) v -= MOD; return *this;}       ModInt& operator -= (const ModInt &other) {v -= other.v; if (v < 0) v += MOD; return *this;}       ModInt& operator *= (const ModInt &other) {v = v * other.v % MOD; return *this;}       ModInt& operator /= (const ModInt &other) {return *this *= inverse(other);}       bool operator == (const ModInt &other) const {return v == other.v;}       bool operator != (const ModInt &other) const {return v != other.v;}       friend ModInt operator + (ModInt a, const ModInt &b) {return a += b;}       friend ModInt operator - (ModInt a, const ModInt &b) {return a -= b;}       friend ModInt operator * (ModInt a, const ModInt &b) {return a *= b;}       friend ModInt operator / (ModInt a, const ModInt &b) {return a /= b;}       friend ModInt operator - (const ModInt &a) {return 0 - a;}       friend ModInt power(ModInt a, long long b) {ModInt ret(1); while (b > 0) {if (b & 1) ret *= a; a *= a; b >>= 1;} return ret;}       friend ModInt inverse(ModInt a) {return power(a, MOD - 2);}       friend istream& operator >> (istream &is, ModInt &m) {is >> m.v; m.v = (-MOD < m.v && m.v < MOD) ? m.v : m.v % MOD; if (m.v < 0) m.v += MOD; return is;}       friend ostream& operator << (ostream &os, const ModInt &m) {return os << m.v;}   };   typedef ModInt<998244353> M;      int main() {       ios_base::sync_with_stdio(false);       cin.tie(NULL);          int n, m;       cin >> n >> m;       vector<vector<int>> d(n, vector<int>(m));       for (int i=0; i<n; i++)           for (int j=0; j<m; j++)               cin >> d[i][j];          M fact = 1;       for (int i=1; i<=n; i++)           fact *= i;          M ret = m * fact;       for (int j=0; j<m; j++) {           vector<int> cnt(n + 1);           for (int i=0; i<n; i++)               cnt[n - d[i][j] + 1]++;           M cur = 1;           int tot = 0;           for (int i=0; i<n; i++) {               tot += cnt[i];               cur *= tot--;           }           ret -= cur;       }       cout << ret / fact <<   n ;          return 0;   }   