#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
struct unionfind{
  vector<int> p;
  unionfind(int N){
    p = vector<int>(N, -1);
  }
  int root(int x){
    if (p[x] < 0){
      return x;
    } else {
      p[x] = root(p[x]);
      return p[x];
    }
  }
  bool same(int x, int y){
    return root(x) == root(y);
  }
  void unite(int x, int y){
    x = root(x);
    y = root(y);
    if (x != y){
      if (p[x] < p[y]){
        swap(x, y);
      }
      p[y] += p[x];
      p[x] = y;
    }
  }
};
int main(){
  int H, W;
  cin >> H >> W;
  vector<vector<int>> A(H, vector<int>(W));
  for (int i = 0; i < H; i++){
    for (int j = 0; j < W; j++){
      cin >> A[i][j];
    }
  }
  vector<tuple<int, int, int>> T;
  for (int i = 0; i < H; i++){
    for (int j = 0; j < W; j++){
      T.push_back(make_tuple(A[i][j], i, j));
    }
  }
  sort(T.begin(), T.end(), greater<tuple<int, int, int>>());
  vector<long long> POW(H + W + 1);
  POW[0] = 1;
  for (int i = 0; i < H + W; i++){
    POW[i + 1] = POW[i] * 2 % MOD;
  }
  long long ans = 0;
  int cnt = H + W - 1;
  unionfind UF(H + W);
  for (int i = 0; i < H * W; i++){
    int x = get<1>(T[i]);
    int y = get<2>(T[i]);
    if (!UF.same(x, H + y)){
      ans += POW[cnt - 1] * get<0>(T[i]);
      ans %= MOD;
      UF.unite(x, H + y);
      cnt--;
    }
  }
  cout << ans << endl;
}