#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
#define ff first
#define ss second
int L, R, M, ans[500005], cnt, D[200005];
bool vis[500005];
pii in[500005];
vector<pii> edge[200005];
void dfs(int x, int c, vector<int> &a, vector<int> &b) {
while (edge[x].size()) {
auto i = edge[x].back(); edge[x].pop_back();
if (vis[i.ss]) continue;
vis[i.ss] = 1;
c ^= 1;
if (c) a.push_back(i.ss);
else b.push_back(i.ss);
D[x]--;
D[i.ff]--;
dfs(i.ff, c, a, b);
}
}
void solve(vector<int> &v) {
for (auto i : v) vis[i] = 0;
vector<int> u;
int flag = 1;
for (auto i : v) {
int x = in[i].ff, y = in[i].ss;
if (!D[x]) u.push_back(x);
if (!D[y]) u.push_back(y);
if (D[x] || D[y]) flag = 0;
edge[x].emplace_back(y, i);
edge[y].emplace_back(x, i);
D[x]++, D[y]++;
}
if (flag) {
for (auto i : u) edge[i].clear(), D[i] = 0;
++cnt;
for (auto i : v) ans[i] = cnt;
return;
}
vector<int> a, b;
for (auto i : u) if (D[i] & 1) dfs(i, 0, a, b);
for (auto i : u) if (D[i]) dfs(i, 0, a, b);
for (auto i : u) edge[i].clear();
solve(a);
solve(b);
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> L >> R >> M;
vector<int> v;
for (int i = 0; i < M; ++i) {
int x, y; cin >> x >> y;
in[i] = pii(x, L + y);
v.emplace_back(i);
}
solve(v);
printf("%d\n", *max_element(ans, ans + M));
for (int i = 0; i < M; ++i) printf("%d\n", ans[i]);
return 0;
}
