#include <bits/stdc++.h>
#define pii pair<int,int>
#define ft first
#define sd second
#define MP make_pair
#define sz(x) ((int)x.size())
using namespace std;
typedef long long ll;
const int N = 5010;
const int M = 500100;
const int oo = 2e9;
bitset<N> mrk[2][N];
int col[M], l, r, m, ans = oo, nm[M], x[M], y[M], X, deg[2][N];
mt19937 rnd(chrono::system_clock().now().time_since_epoch().count());
void potential(){
int cur = 0;
for (int it = 0; it < m; it++){
int i = nm[it];
int c = (mrk[0][x[i]] & mrk[1][y[i]])._Find_first();
col[i] = c;
cur = max(cur, c);
if (cur >= X) {
for (int jt = 0; jt < it; jt++){
int j = nm[jt];
mrk[0][x[j]][col[j]] = mrk[1][y[j]][col[j]] = 1;
}
shuffle(nm, nm + m, rnd);
return;
}
mrk[0][x[i]][c] = mrk[1][y[i]][c] = 0;
}
cout << cur + 1 << '\n';
for (int i = 0; i < m; i++)
cout << col[i] + 1 << '\n';
exit(0);
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> l >> r >> m;
for (int i = 0; i < m; i++){
cin >> x[i] >> y[i];
x[i]--; y[i]--;
deg[0][x[i]]++;
deg[1][y[i]]++;
nm[i] = i;
}
int mex = 0;
for (int i = 0; i < max(l, r); i++) {
mex = max(mex, deg[0][i]);
mex = max(mex, deg[1][i]);
}
X = 1;
while (X < mex) X += X;
for (int i = 0; i < max(l, r); i++)
for (int j = 0; j < max(l, r); j++){
mrk[0][i][j] = mrk[1][i][j] = 1;
}
for (;;)
potential();
return 0;
}
