#include <bits/stdc++.h>   
#define rep(i, n) for(long long int i = 0; i < n; i++)
#define _rep(i, m, n) for(long long int i = m; i < n; i++)
using namespace std;
typedef long long ll;
typedef pair<int, int> P;
const ll mod = 1000000007;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};
     
ll gcd(ll A, ll B){
    if(B == 0)return A;
    return gcd(B, A % B);
}
ll lcm(ll A, ll B){
    return A * B / gcd(A, B);
}
template <typename T>
T pow(T a, ll n, T e = 1) {
    T ret = e;
    while (n) {
        if (n & 1) ret *= a;
        a *= a;
        n >>= 1;
    }
    return ret;
}
 
template <int mod>
struct ModInt {
    int x;
    ModInt() : x(0) {}
    ModInt(long long x_) {
        if ((x = x_ % mod + mod) >= mod) x -= mod;
    }
    ModInt& operator+=(ModInt rhs) {
        if ((x += rhs.x) >= mod) x -= mod;
        return *this;
    }
    ModInt& operator-=(ModInt rhs) {
        if ((x -= rhs.x) < 0) x += mod;
        return *this;
    }
    ModInt& operator*=(ModInt rhs) {
        x = (unsigned long long)x * rhs.x % mod;
        return *this;
    }
    ModInt& operator/=(ModInt rhs) {
        x = (unsigned long long)x * rhs.inv().x % mod;
        return *this;
    }
 
    ModInt operator-() const { return -x < 0 ? mod - x : -x; }
    ModInt operator+(ModInt rhs) const { return ModInt(*this) += rhs; }
    ModInt operator-(ModInt rhs) const { return ModInt(*this) -= rhs; }
    ModInt operator*(ModInt rhs) const { return ModInt(*this) *= rhs; }
    ModInt operator/(ModInt rhs) const { return ModInt(*this) /= rhs; }
    bool operator==(ModInt rhs) const { return x == rhs.x; }
    bool operator!=(ModInt rhs) const { return x != rhs.x; }
    ModInt inv() const { return pow(*this, mod - 2); }
 
    friend ostream& operator<<(ostream& s, ModInt<mod> a) {
        s << a.x;
        return s;
    }
    friend istream& operator>>(istream& s, ModInt<mod>& a) {
        s >> a.x;
        return s;
    }
};
 
using mint = ModInt<1000000007>;
using Graph = vector<vector<int>>;
Graph G;
/*------------------------------------------------------------------*/
void dfs(const Graph &G, int v, int pa){

}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n; cin >> n;
    Graph G(n);
    vector<pair<int,int>> vp;
    rep(i, n - 1){
        int a, b; cin >> a >> b;
        a--, b--;
        G[a].push_back(b);
        G[b].push_back(a);
        vp.emplace_back(a, b);
    }
    int max_child = 0;
    rep(i, n){
        max_child = max((int)G[i].size(), max_child);
    }
    cout << max_child << endl;
    map<pair<int,int>,int> mp;
    vector<int> co(n);
    vector<bool> seen(n, false);
    
    queue<int> q;
    q.push(0);
    seen[0] = true;
    while(!q.empty()){
        int v = q.front(); q.pop();
        int cur = 1;
        for(auto next_v : G[v]){
            if(seen[next_v]) continue;
            if(cur == co[v]) cur++;
            mp[{next_v, v}] = cur++;
            mp[{v, next_v}] = mp[{next_v, v}];
            co[next_v] = mp[{v, next_v}];
            seen[next_v] = true;
            q.push(next_v);
        }
    }
    for(auto p : vp){
        cout << mp[p] << endl;
    }
    return 0;    
}

Measured memory_bytes: 22340