from operator import itemgetter
from itertools import *
from bisect import *
from collections import *
from heapq import *
import sys

sys.setrecursionlimit(10 ** 6)

def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def SI(): return sys.stdin.readline()[:-1]
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
int1 = lambda x: int(x) - 1
def MI1(): return map(int1, sys.stdin.readline().split())
def LI1(): return list(map(int1, sys.stdin.readline().split()))
p2D = lambda x: print(*x, sep="\n")
dij = [(1, 0), (0, 1), (-1, 0), (0, -1)]

md=10**9+7
n_max = 200005
fac = [1]
for i in range(1, n_max + 1): fac.append(fac[-1] * i % md)
ifac = [1] * (n_max + 1)
ifac[n_max] = pow(fac[n_max], md - 2, md)
for i in range(n_max - 1, 1, -1): ifac[i] = ifac[i + 1] * (i + 1) % md

memo={}
def main():
    def dfs(i=0,x=0,y=0,log=[]):
        if i==k:
            if x!=gx or y!=gy:return 0
            res=fac[sum(log)]
            for c in log:res=res*ifac[c]%md
            return res
        t=(i,x,y)
        if t in memo:return memo[t]
        res=0
        dx,dy,c=xyc[i]
        for j in range(c+1):
            res=(res+dfs(i+1,x+dx*j,y+dy*j,log+[j]))%md
        memo[t]=res
        return res

    gx,gy,k=MI()
    xyc=LLI(k)
    print(dfs())

main()