import java.io.IOException;
import java.io.InputStream;
import java.util.*;

public class Main {

    static class Edge implements Comparable<Edge> {
        int from, to, color, id;

        public Edge(int from, int to, int color, int id) {
            this.from = from;
            this.to = to;
            this.color = color;
            this.id = id;
        }

        @Override
        public int compareTo(Edge o) {
            return id - o.id;
        }
    }

    static class Pair {
        int id, prevColor;

        public Pair(int id, int prevColor) {
            this.id = id;
            this.prevColor = prevColor;
        }
    }

    static int N;
    static List<List<Edge>> graph;
    static boolean[] visited;
    static List<Edge> edges;

    static void bfs() {
        visited = new boolean[N];
        visited[0] = true;
        Deque<Pair> deq = new ArrayDeque<>();
        deq.offer(new Pair(0, 0));

        while (!deq.isEmpty()) {
            Pair node = deq.poll();
            int color = 1;
            int prevColor = node.prevColor;
            if (color == prevColor) ++color;

            for (Edge e : graph.get(node.id)) {
                if (visited[e.to]) continue;
                visited[e.to] = true;
                e.color = color++;
                edges.add(e);
                deq.offer(new Pair(e.to, e.color));

                if (color == prevColor) ++color;
            }
        }
    }

    public static void main(String[] args) {
        FastScanner fs = new FastScanner();
        N = fs.nextInt();
        graph = new ArrayList<>();
        edges = new ArrayList<>();
        for (int i = 0; i < N; ++i) graph.add(new ArrayList<>());
        for (int i = 0; i < N-1; ++i) {
            int a = fs.nextInt() - 1;
            int b = fs.nextInt() - 1;
            graph.get(a).add(new Edge(a, b, 0, i));
            graph.get(b).add(new Edge(b, a, 0, i));
        }

        int maxDeg = 0;
        for (int i = 0; i < N; ++i) maxDeg = Math.max(maxDeg, graph.get(i).size());

        bfs();

        System.out.println(maxDeg);
        Collections.sort(edges);
        for (int i = 0; i < N-1; ++i) {
            System.out.println(edges.get(i).color);
        }
    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;

        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }

        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}

        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }

        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }

        public double nextDouble() { return Double.parseDouble(next());}
    }

}

Measured memory_bytes: 60568