#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define FOR(i,a,b) for (int i=(a);i<(b);++i)
#define REP(a,b) for(int a=0;a<(b);++a)
#define REP1(i,n) for(int i=1;i<=(n);++i)
#define debug(x) cerr<<#x<<": "<<x<<'\n'
#define all(x) (x).begin(),(x).end()
#define YES() printf("YES\n")
#define NO() printf("NO\n")
#define isYES(x) printf("%s\n",(x) ? "YES" : "NO")
#define Yes() printf("Yes\n")
#define No() printf("No\n")
#define isYes(x) printf("%s\n",(x) ? "Yes" : "No")
#define SZ(x) ((int)(x).size())
#define pb push_back
#define mp make_pair
#define INF (1<<29)
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
#define X first
#define Y second
using namespace std;
typedef pair<int, int> P;
typedef pair<ll, ll> LP;
typedef pair<int, P> PP;
typedef pair<ll, LP> LPP;


template<class T=int>
T in(){T x;cin>>x;return (x);}
template<class T>
void print(T& x){cout<<x<<'\n';}

const int MOD =(int)1e9+7;
const int MAX =510000;
ll fac[MAX],finv[MAX],inv[MAX];
void COMint(){
    fac[0]=fac[1]=1;
    finv[0]=finv[1]=1;
    inv[1]=1;
    for(int i=2;i<MAX;i++){
        fac[i]=fac[i-1]*i%MOD;
        inv[i]=MOD-inv[MOD%i]*(MOD/i)%MOD;
        finv[i]=finv[i-1]*inv[i]%MOD;
    }
}
ll COM(int n,int k){
    if(n<k) return 0;
    if(n<0||k<0)return 0;
    return fac[n]*(finv[k]*finv[n-k]%MOD)%MOD;
}
ll gcd(ll a,ll b){
    if(b==0)return a;
    if(a>b){
        swap(a,b);
    }
    return gcd(a,b%a);
}
ll lcm(ll a,ll b){
    ll g;g=gcd(a,b);
    return a*b/g;
}
bool compare_by_b(pair<int, int> a, pair<int, int> b) {
    if(a.second != b.second){
        return a.second < b.second;
    }else{
        return a.first < b.first;
    }
}

bool compare_by_a(pair<int, int> a, pair<int, int> b) {
    if(a.first != b.first){
        return a.first < b.first;
    }else{
        return a.second < b.second;
    }
}
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

ll RS(ll N,ll P,ll M){
    if(P==0){
        return 1;
    }else{
        if(P%2==0){
            ll t=RS(N,P/2,M);
            return t*t%M;
        }else{
            return N*RS(N,P-1,M)%M;
        }
    }
}
vector<vector<int>> vec;
vector<int> ans;
map<P,int> m;
int ans_max=0;
void DFS(int x,int y=-1,int c=-1){
    int k=1;
    REP(i,vec[x].size()){
        if(vec[x][i]==y)continue;
        if(k==c)k++;
        ans[m[P(x,vec[x][i])]]=k;
        ans_max=max(ans_max,k);
        DFS(vec[x][i],x,k);
        k++;
    }
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N=in();
    vec.resize(N);
    ans.resize(N-1);
    REP(i,N-1){
        int a,b;
        cin>>a>>b;
        --a;--b;
        m[P(a,b)]=i;
        m[P(b,a)]=i;
        vec[a].pb(b);
        vec[b].pb(a);
    }
    DFS(0);
    cout<<ans_max<<endl;
    REP(i,N-1){
        cout<<ans[i]<<endl;
    }
    return 0;
}


Measured memory_bytes: 18944