#include<bits/stdc++.h>
using namespace std;
int n,m,k;
int a,b,c;
int ans;
bool book[105][105];
bool used[105];
int belong[105];
bool find(int x)
{
    for(int i=1;i<=m;i++)
    {
        if(book[x][i]&&!used[i])
        {
            used[i]=1;
            if(!belong[i]||find(belong[i]))
            {
                belong[i]=x;
                return 1;
            }
        }
    }
    return 0;
}
int main()
{
    while(1)
    {
        ans=0;
        memset(book,0,sizeof(book));
        memset(belong,0,sizeof(belong));
        cin>>n;
        if(!n)
            return 0;
        cin>>m>>k;
        while(k--)
        {
            scanf("%d %d %d",&a,&b,&c);
            book[b][c]=1;
        }
        for(int i=1;i<=n;i++)
        {
            memset(used,0,sizeof(used));
            if(find(i))
                ans++;
        }
        cout<<ans<<endl;
    }
}