#![allow(non_snake_case)]
#![allow(dead_code)]
#![allow(unused_macros)]
#![allow(unused_imports)]

use std::cmp::*;
use std::collections::*;

macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
    ($iter:expr, mut $var:ident : $t:tt $($r:tt)*) => {
        let mut $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    }
}

macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

macro_rules! chmax {
    ($x:expr, $e:expr) => {
        if $x < $e {
            $x = $e;
        }
    };
}
macro_rules! chmin {
    ($x:expr, $e:expr) => {
        if $x > $e {
            $x = $e;
        }
    };
}

const INF: i64 = 1 << 60;

struct Solver {
    graph: Vec<Vec<usize>>,
    edges: Vec<Vec<usize>>,
    colors: Vec<i64>,
    visited: HashSet<usize>,
    K: usize,
}

impl Solver {
    fn new(N: usize, K: usize, edges: Vec<Vec<usize>>, graph: Vec<Vec<usize>>) -> Solver {
        let colors = vec![-1; N-1];
        Solver { graph: graph, edges: edges, colors: colors, K: K, visited: HashSet::new() }
    }
    fn dfs(&mut self, v: usize) {
        if self.visited.contains(&v) {
            return;
        }
        self.visited.insert(v);
        let mut used = 0;
        for &e in &self.edges[v] {
            if self.colors[e] != -1 {
                used = self.colors[e];
            }
        }
        let mut color = used + 1;
        if color > self.K as i64 {
            color = 1;
        }
        for &e in &self.edges[v] {
            if self.colors[e] == -1 {
                self.colors[e] = color;
                color += 1;
                if color == used {
                    color += 1;
                }
                if color > self.K as i64 {
                    color = 1;
                }
            }
        }
        for vi in self.graph[v].clone() {
            self.dfs(vi);
        }
    }
    fn solve(&mut self) {
        unimplemented!();
    }
}

fn main() {
    input!{
        N: usize,
        ab: [(usize1, usize1); N-1],
    }
    let mut graph = vec![Vec::new(); N];
    let mut edges = vec![Vec::new(); N];
    let mut deg = vec![0; N];
    for (i, (a, b)) in ab.into_iter().enumerate() {
        graph[a].push(b);
        graph[b].push(a);
        edges[a].push(i);
        edges[b].push(i);
        deg[a] += 1;
        deg[b] += 1;
    }
    let K = deg.into_iter().max().unwrap();
    let mut solver = Solver::new(N, K, edges, graph);
    solver.dfs(0);
    println!("{}", K);
    for c in solver.colors {
        println!("{}", c);
    }
}


Measured memory_bytes: 34684