#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;
using mint = modint998244353;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  vector<tuple<int, int, int>> a(n * m);
  rep(i, n) rep(j, m) {
    int x;
    cin >> x;
    a[i * m + j] = {x, i, j};
  }
  sort(rall(a));
  dsu uf(n + m);
  const mint inv2 = mint(2).inv();
  mint now = mint(2).pow(n + m - 2);
  mint ans;
  for(auto [x, i, j]: a) {
    if (!uf.same(i, n + j)) {
      ans += x * now;
      uf.merge(i, n + j);
      now *= inv2;
    }
  }
  cout << ans.val() << '\n';
}