#include <cctype>
#include <cfloat>
#include <climits>
#include <cmath>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <valarray>
#include <vector>

#if __cplusplus >= 201103L
#include <array>
#include <forward_list>
#include <random>
#include <regex>
#include <scoped_allocator>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <unordered_map>
#include <unordered_set>
#endif

#define F first
#define S second
#define MP make_pair
#define pb push_back
#define all(a) a.begin(), a.end()
#define lcm( a, b ) (a)/__gcd((a),(b))*(b)
#define endl '\n'

using namespace std;

typedef long long LL;
typedef pair< int, int > P;
typedef pair< LL, LL > LP;
typedef pair< int, P > iP;
typedef pair< P, P > PP;

static const int INF = INT_MAX;
static const LL LINF = LLONG_MAX;
static const int MIN = INT_MIN;
static const LL LMIN = LLONG_MIN;
static const int MOD = 1000000007;
static const int SIZE = 200005;

const int dx[] = {0, -1, 1, 0};
const int dy[] = {-1, 0, 0, 1};

vector< int > Div( int n ) {
    vector< int > ret;
    for( int i = 1; i * i <= n; ++i ) {
        if( n % i == 0 ) {
            ret.pb( i );

            if( i * i != n ) ret.pb( n / i );
        }
    }
    sort( all( ret ) );
    return ret;
}
void dfs( int pos, int color, int be );

vector< int > tree[SIZE];

int col[SIZE];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;
    vector< P > edge;
    for( int i = 0; i < n - 1; ++i ) {
        int a, b;
        cin >> a >> b;
        if( a > b ) swap(a, b);
        edge.pb( MP( a, b ) );
        tree[a].pb( b );
        tree[b].pb( a );

    }
    
    map< P, int > mp;

    for( int i = 1; i <= n; ++i ) {
        priority_queue< int, vector< int >, greater< int > > q;
        int cnt = 1;
        for( int j = 0; j < tree[i].size(); ++j ) {
            int x, y;
            x = i; y = tree[i][j];
            if( x > y ) swap(x, y);
            if( mp[MP(x, y)] != 0 ) {
                q.push(mp[MP(x, y)]);

            }
        }

        for( int j = 0; j < tree[i].size(); ++j ) {
            int x, y;
            x = i; y = tree[i][j];
            if( x > y ) swap(x, y);
            if( mp[MP(x, y)] != 0 ) {
                continue;

            }
            while( !q.empty() && cnt == q.top() ) {
                ++cnt;
                if( !q.empty() && cnt >= q.top() ) q.pop();

            }
            mp[MP(x, y)] = cnt;
            ++cnt;

        }
    }
    int mx = 0;
    for( int i = 0; i < edge.size(); ++i ) {
        mx = max( mx, mp[MP(edge[i].F, edge[i].S)]);

    }
    cout << mx << endl;
    for( int i = 0; i < edge.size(); ++i ) {
        cout << mp[MP(edge[i].F, edge[i].S)] << endl;

    }

    return 0;
}



Measured memory_bytes: 15480