#include "bits/stdc++.h"
using namespace std;
#ifdef _DEBUG
#include "dump.hpp"
#else
#define dump(...)
#endif

#define int long long
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(c) begin(c),end(c)
const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = 1000000007;
template<class T> bool chmax(T &a, const T &b) { if (a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, const T &b) { if (b < a) { a = b; return true; } return false; }

template<typename T>
vector<T> gen_v(size_t a) { return vector<T>(a); }
template<typename T, typename ...Ts>
auto gen_v(size_t a, Ts... ts) { return vector<decltype(gen_v<T>(ts...))>(a, gen_v<T>(ts...)); }
template<typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type
fill_v(T &t, const V &v) { t = v; }
template<typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type
fill_v(T &t, const V &v) { for (auto &e : t) fill_v(e, v); }

using Weight = int;
struct Edge {
	int s, d; Weight w;
	Edge() {};
	Edge(int s, int d, Weight w) : s(s), d(d), w(w) {};
};
bool operator<(const Edge &e1, const Edge &e2) { return e1.w == e2.w ? (e1.s == e2.s ? e1.d < e2.d : e1.s < e2.s) : e1.w < e2.w; }
bool operator>(const Edge &e1, const Edge &e2) { return e2 < e1; }
inline ostream &operator<<(ostream &os, const Edge &e) { return (os << '(' << e.s << ", " << e.d << ", " << e.w << ')'); }

using Edges = vector<Edge>;
using Graph = vector<Edges>;
using Array = vector<Weight>;
using Matrix = vector<Array>;

void addArc(Graph &g, int s, int d, Weight w = 1) {
	g[s].emplace_back(s, d, w);
}
void addEdge(Graph &g, int a, int b, Weight w = 1) {
	addArc(g, a, b, w);
	addArc(g, b, a, w);
}

auto getEdges = [](const Graph &g) {
	Edges ret;
	for (auto &es : g)
		for (auto &e : es)
			ret.emplace_back(e);
	return ret;
};

signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	int N; cin >> N;
	Graph g(N);
	vector<int> a(N - 1), b(N - 1); rep(i, 0, N - 1) {
		cin >> a[i] >> b[i];
		a[i]--, b[i]--;
		addEdge(g, a[i], b[i]);
	}

	//vector<set<int>> S(N);

	//vector<set<int>> p(N);
	//rep(i, 0, N - 1) {
	//	p[a[i]].emplace(b[i]);
	//	p[b[i]].emplace(a[i]);
	//}

	//queue<int> q;
	//rep(i, 0, N) {
	//	if (p[i].size() == 1)
	//		q.emplace(i);
	//}

	//vector<int> color(N - 1);
	//while (q.size()) {
	//	int x = q.front(); q.pop();
	//	int y = *p[x].begin();
	//	S[y];
	//}

	map<pair<int, int>, int> id;
	rep(i, 0, N - 1) {
		id[make_pair(a[i], b[i])] = i;
		id[make_pair(b[i], a[i])] = i;
	}
	vector<int> color(N - 1);

	auto bfs = [&](const Graph &g, int s, Array &dist) {
		int n = g.size();
		vector<bool> vis(n);
		vector<int> prev(n, -1);
		dist.assign(n, INF); dist[s] = 0;
		using State = tuple<Weight, int, int, int>;
		queue<State> q;
		q.emplace(0, s, -1, -1);
		while (q.size()) {
			Weight d; int v, p, pc; tie(d, v, p, pc) = q.front(); q.pop();
			vis[v] = true;
			prev[v] = p;
			int c = 0;
			for (auto &e : g[v]) {
				if (vis[e.d])continue;
				if (dist[e.d] > dist[v] + e.w) {
					dist[e.d] = dist[v] + e.w;
					if (c == pc)c++;
					color[id[make_pair(v, e.d)]] = c;
					q.emplace(dist[e.d], e.d, v, c);
					c++;
				}
			}
		}
		return prev;
	};

	Array dist;
	bfs(g, 0, dist);

	dump(color);

	cout << *max_element(all(color)) + 1 << endl;
	rep(i, 0, color.size()) { cout << color[i] + 1 << endl; }

	return 0;
}

Measured memory_bytes: 25984