import java.util.Arrays;
import java.util.Scanner;

public class Main {
	public static final long MOD = 1000000007;
	
	public static long mod_pow(long a, long e, long m){
		if(e == 0){
			return 1;
		}else if(e % 2 == 0){
			long ret = mod_pow(a, e / 2, m);
			return (ret * ret) % m;
		}else{
			return (mod_pow(a, e - 1, m) * a) % m;
		}
	}
	
	public static long mod_inv(long a, long p){
		return mod_pow(a, p - 2, p);
	}
	
	public static long dfs(int deep, int limit, int[] using, int[] xs, int[] ys, int[] ns, int gx, int gy, long x, long y){
		if(deep >= limit){
			if(gx == x && gy == y){
				final int use_sum = Arrays.stream(using).sum();
				if(use_sum == 0){ return 0; }
				long upper = 1;
				
				for(int i = 1; i <= use_sum; i++){
					upper *= i;
					upper %= MOD;
				}
				
				long lower = 1;
				for(int part = 0; part < limit; part++){
					for(int i = 1; i <= using[part]; i++){
						lower *= i;
						lower %= MOD;
					}
				}
				
				return (upper * mod_inv(lower, MOD)) % MOD;
			}else{
				return 0;
			}
		}else{
			long ret = 0;
			for(int i = 0; i <= ns[deep]; i++){
				using[deep] = i;
				ret += dfs(deep + 1, limit, using, xs, ys, ns, gx, gy, x + xs[deep] * i, y + ys[deep] * i);
			}
			
			return ret;
		}
	}
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		final int gx = sc.nextInt();
		final int gy = sc.nextInt();
		final int K = sc.nextInt();
		
		int[] xs = new int[K];
		int[] ys = new int[K];
		int[] ns = new int[K];
		for(int i = 0; i < K; i++){
			xs[i] = sc.nextInt();
			ys[i] = sc.nextInt();
			ns[i] = sc.nextInt();
		}
		
		System.out.println(dfs(0, K, new int[K], xs, ys, ns, gx, gy, 0, 0));
		
	}
}