h, w, k = map(int, input().split()) mod = 998244353 ls = [list(map(int, input().split())) for _ in range(k)] g = [[0] * w for _ in range(h)] for x, y, v in ls: g[x-1][y-1] = v ans = 0 for i in range(h): for j in range(w): for x in range(h): for y in range(w): if x + y >= i + j and x - y >= i - j: ans += g[x][y] print(ans % mod)