using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
    private int N;
    private List<E>[] Edge;

    private int Color;
    private int[] Ans;

    public void Solve()
    {
        var sc = new Scanner();
        N = sc.NextInt();
        Edge = new List<E>[N];
        for (int i = 0; i < N; i++)
        {
            Edge[i] = new List<E>();
        }

        for (int i = 0; i < N - 1; i++)
        {
            int a = sc.NextInt() - 1;
            int b = sc.NextInt() - 1;
            Edge[a].Add(new E(b, i));
            Edge[b].Add(new E(a, i));
        }

        
        Ans = new int[N - 1];
        Search(0,-1);
        Color = Ans.Max();
        Console.WriteLine(Color);
        Console.WriteLine(string.Join("\n",Ans));
    }

    private void Search(int i, int parent)
    {
        int c = 1;

        int toParent = -1;
        foreach (var e in Edge[i])
        {
            if (e.B == parent)
            {
                toParent = e.Index;
            }
        }
        
        foreach (E e in Edge[i])
        {
            if (e.B == parent) continue;
            if (parent != -1 && Ans[toParent] == c)
            {
                c++;
            }

            Ans[e.Index] = c;
            Search(e.B,i);
            c++;
        }
    }


    public static void Main(string[] args)
    {
        new Program().Solve();
    }
}

struct E
{
    public int B, Index;

    public E(int b, int i)
    {
        B = b;
        Index = i;
    }
}


class Scanner
{
    public Scanner()
    {
        _pos = 0;
        _line = new string[0];
    }

    const char Separator = ' ';
    private int _pos;
    private string[] _line;

    #region スペース区切りで取得

    public string Next()
    {
        if (_pos >= _line.Length)
        {
            _line = Console.ReadLine().Split(Separator);
            _pos = 0;
        }

        return _line[_pos++];
    }

    public int NextInt()
    {
        return int.Parse(Next());
    }

    public long NextLong()
    {
        return long.Parse(Next());
    }

    public double NextDouble()
    {
        return double.Parse(Next());
    }

    #endregion

    #region 型変換

    private int[] ToIntArray(string[] array)
    {
        var result = new int[array.Length];
        for (int i = 0; i < array.Length; i++)
        {
            result[i] = int.Parse(array[i]);
        }

        return result;
    }

    private long[] ToLongArray(string[] array)
    {
        var result = new long[array.Length];
        for (int i = 0; i < array.Length; i++)
        {
            result[i] = long.Parse(array[i]);
        }

        return result;
    }

    private double[] ToDoubleArray(string[] array)
    {
        var result = new double[array.Length];
        for (int i = 0; i < array.Length; i++)
        {
            result[i] = double.Parse(array[i]);
        }

        return result;
    }

    #endregion

    #region 配列取得

    public string[] Array()
    {
        if (_pos >= _line.Length)
            _line = Console.ReadLine().Split(Separator);

        _pos = _line.Length;
        return _line;
    }

    public int[] IntArray()
    {
        return ToIntArray(Array());
    }

    public long[] LongArray()
    {
        return ToLongArray(Array());
    }

    public double[] DoubleArray()
    {
        return ToDoubleArray(Array());
    }

    #endregion
}

Measured memory_bytes: 32812