n,m,q = map(int,input().split())
l1,l2 = [],[]
for _ in range(q):
    a,b = map(int,input().split())
    l1.append((a,b))
    l2.append((b,a))
import bisect
def lis(l):
    l.sort(key = lambda x:(x[0],x[1]))
    flg = 0
    ll = []
    for i in range(q):
        if l[i][0] != flg:
            ll.append(l[i][1])
    nn = len(ll)
    dp = []
    for i in range(nn):
        idx = bisect.bisect(dp,ll[i])
#         print(i,ll[i],idx,dp)
        if idx == len(dp):
            dp.append(ll[i])
        else:
            dp[idx] = ll[i]
#     print(l,dp)
    return len(dp)
print(max(lis(l1),lis(l2)))