// github.com/Johniel/contests
// yukicoder/2225/main.cpp

#include <bits/stdc++.h>

#define each(i, c) for (auto& i : c)
#define unless(cond) if (!(cond))
// #define endl "\n"

using namespace std;

template<typename P, typename Q> ostream& operator << (ostream& os, pair<P, Q> p) { os << "(" << p.first << "," << p.second << ")"; return os; }
template<typename P, typename Q> istream& operator >> (istream& is, pair<P, Q>& p) { is >> p.first >> p.second; return is; }
template<typename T> ostream& operator << (ostream& os, vector<T> v) { os << "("; for (auto& i: v) os << i << ","; os << ")"; return os; }
template<typename T> istream& operator >> (istream& is, vector<T>& v) { for (auto& i: v) is >> i; return is; }
template<typename T> ostream& operator << (ostream& os, set<T> s) { os << "#{"; for (auto& i: s) os << i << ","; os << "}"; return os; }
template<typename K, typename V> ostream& operator << (ostream& os, map<K, V> m) { os << "{"; for (auto& i: m) os << i << ","; os << "}"; return os; }
template<typename E, size_t N> istream& operator >> (istream& is, array<E, N>& a) { for (auto& i: a) is >> i; return is; }
template<typename E, size_t N> ostream& operator << (ostream& os, array<E, N>& a) { os << "[" << N << "]{"; for (auto& i: a) os << i << ","; os << "}"; return os; }

template<typename T> inline T setmax(T& a, T b) { return a = std::max(a, b); }
template<typename T> inline T setmin(T& a, T b) { return a = std::min(a, b); }

__attribute__((constructor)) static void ___initio(void) { ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.setf(ios_base::fixed); cout.precision(15); return ; }

using lli = long long int;
using ull = unsigned long long;
using str = string;
template<typename T> using vec = vector<T>;

constexpr array<int, 8> di({0, 1, -1, 0, 1, -1, 1, -1});
constexpr array<int, 8> dj({1, 0, 0, -1, 1, -1, -1, 1});
constexpr lli mod = 998244353;

int main(int argc, char *argv[])
{
  int h, w, k;
  while (cin >> h >> w >> k) {
    map<pair<int, int>, lli> m;
    for (int i = 0; i < k; ++i) {
      pair<int, int> p;
      lli w;
      cin >> p >> w;
      --p.first;
      --p.second;
      m[p] = w;
    }
    lli z = 0;
    for (int i = 0; i < h; ++i) {
      for (int j = 0; j < w; ++j) {
        for (int x = 0; x < h; ++x) {
          for (int y = 0; y < w; ++y) {
            pair<int, int> p = make_pair(x, y);
            if (m.count(p) && x + y >= i + j && x - y >= i - j) {
              (z += m[p]) %= mod;
            }
          }
        }
      }
    }
    cout << z << endl;
  }
  return 0;
}