#include "bits/stdc++.h"
// Begin Header {{{
#define all(x)          (x).begin(), (x).end()
#define rep(i, s, n)    for (i64 i = (s), i##_limit = (n); i < i##_limit; ++i)
#define repr(i, s, t)   for (i64 i = (s), i##_limit = (t); i >= i##_limit; --i)
#define var(type, ...)  type __VA_ARGS__; read(__VA_ARGS__);
#ifndef DBG
#define dump(...)
#endif
using namespace std;
using i64 = int_fast64_t;
using pii = pair<i64, i64>;
template <class T, class U> inline bool chmax(T &a, const U &b) { return b > a && (a = b, true); }
template <class T, class U> inline bool chmin(T &a, const U &b) { return b < a && (a = b, true); }
constexpr int INF  = 0x3f3f3f3f;
constexpr i64 LINF = 0x3f3f3f3f3f3f3f3fLL;

template <class T>
inline vector<T> makeV(const T &initValue, size_t sz) {
    return vector<T>(sz, initValue);
}

template <class T, class... Args>
inline auto makeV(const T &initValue, size_t sz, Args... args) {
    return vector<decltype(makeV<T>(initValue, args...))>(sz, makeV<T>(initValue, args...));
}

template <class T>
inline istream& operator>> (istream &is, vector<T> &vec) {
    for (auto &e : vec) is >> e;
    return is;
}

inline void read() {}

template <class Head, class... Tail>
inline void read(Head &head, Tail&... tail) { cin >> head; read(tail...); }

inline void print() { cout << "\n"; }

template <class Head, class... Tail>
inline void print(Head &&head, Tail&&... tail) {
    cout << head;
    if (sizeof...(tail)) cout << ' ';
    print(forward<Tail>(tail)...);
}

template <class T>
inline ostream& operator<< (ostream &os, const vector<T> &vec) {
    static constexpr const char *delim[] = { " ", "" };
    for (const auto &e : vec) os << e << delim[&e == &vec.back()];
    return os;
}

template <class Container>
struct Rev {
    Container &x_;
    inline Rev(Container &x): x_(x) {}
    inline auto begin() { return rbegin(x_); }
    inline auto end() { return rend(x_); }
};
// }}} End Header

vector<vector<int>> G;
vector<vector<int>> id;
vector<int> deg;

vector<int> ans;
bool visited[100010];

void dfs(int u, int color) {
    visited[u] = true;
    int c = 1;
    rep(i, 0, G[u].size()) {
        if (visited[G[u][i]]) continue;
        if (c == color) ++c;
        ans[id[u][i]] = c;
        dfs(G[u][i], c);
        ++c;
    }
    return;
}


signed main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);

    var(int, N);
    G.resize(N);
    id.resize(N);
    deg.resize(N);
    ans.resize(N - 1);

    rep(i, 0, N-1) {
        var(int, a, b);
        --a, --b;
        G[a].push_back(b);
        G[b].push_back(a);
        id[a].push_back(i);
        id[b].push_back(i);
        deg[a] += 1;
        deg[b] += 1;
    }


    vector<int> nodes(N);
    iota(all(nodes), 0);
    sort(all(nodes), [](int u, int v) { return deg[u] > deg[v]; });

    dump(deg);
    dump(nodes);
    rep(i, 0, N) {
        dump(id[i]);
    }

    const int R = nodes[0];
    const int K = deg[R];

    dump(R, K);

    int color = 1;
    rep(i, 0, G[R].size()) {
        ans[id[R][i]] = color;
        visited[R] = true;
        dfs(G[R][i], color);
        ++color;
    }

    print(K);
    rep(i, 0, N-1) {
        print(ans[i]);
    }

    return 0;
}



Measured memory_bytes: 12928