You are given an unweighted tree with n vertices. Recall that a tree is a connected undirected graph without cycles.

Your task is to choose three distinct vertices a, b, c on this tree such that the number of edges which belong to at least one of the simple paths between a and b, b and c, or a and c is the maximum possible. See the notes section for a better understanding.

The simple path is the path that visits each vertex at most once.

Input

The first line contains one integer number n (3 ≤ n ≤ 2 ⋅ 10^5) — the number of vertices in the tree. 

Next n - 1 lines describe the edges of the tree in form a_i, b_i (1 ≤ a_i, b_i ≤ n, a_i ≠ b_i). It is guaranteed that given graph is a tree.

Output

In the first line print one integer res — the maximum number of edges which belong to at least one of the simple paths between a and b, b and c, or a and c.

In the second line print three integers a, b, c such that 1 ≤ a, b, c ≤ n and a ≠, b ≠ c, a ≠ c.

If there are several answers, you can print any.

Example

Input


8
1 2
2 3
3 4
4 5
4 6
3 7
3 8


Output


5
1 8 6

Note

The picture corresponding to the first example (and another one correct answer):

<image>

If you choose vertices 1, 5, 6 then the path between 1 and 5 consists of edges (1, 2), (2, 3), (3, 4), (4, 5), the path between 1 and 6 consists of edges (1, 2), (2, 3), (3, 4), (4, 6) and the path between 5 and 6 consists of edges (4, 5), (4, 6). The union of these paths is (1, 2), (2, 3), (3, 4), (4, 5), (4, 6) so the answer is 5. It can be shown that there is no better answer.
import java.util.*;
import java.io.*;
import java.text.*;
public class Main{
    //SOLUTION BEGIN
    //Into the Hardware Mode
    void pre() throws Exception{}
    void solve(int TC)throws Exception {
        int n = ni();
        int[] from = new int[n-1], to = new int[n-1];
        for(int i = 0; i< n-1; i++){from[i] = ni()-1;to[i] = ni()-1;}
        int[][] g = makeU(n, from, to);
        int root = 0;
        Queue<Integer> q = new ArrayDeque<>();
        q.add(root);
        int[] d = new int[n];
        Arrays.fill(d, n<<1);
        d[root] = 0;
        while(!q.isEmpty()){
            int r = q.poll();
            root = r;
            for(int v:g[r]) {
                if (d[v] > d[r] + 1) {
                    d[v] = d[r] + 1;
                    q.add(v);
                }
            }
        }
        int a = root;
        q.add(root);
        Arrays.fill(d, n<<1);
        d[root] = 0;
        int[] p = new int[n];Arrays.fill(p, -1);
        while(!q.isEmpty()){
            int r = q.poll();
            root = r;
            for(int v:g[r])
                if(d[v] >d[r]+1){
                    d[v] = d[r]+1;
                    p[v] = r;
                    q.add(v);
                }
        }
        int b = root;
        boolean[] path = new boolean[n];
        int ans = -1;
        while(root != -1){ans++;path[root] = true;root = p[root];}
        Arrays.fill(d, n<<1);
        int c = n-1;
        if(a == c || b == c)c--;
        if(a == c || b == c)c--;
        for(int i = 0; i< n; i++)if(path[i]){
            d[i] = 0;
            fill(g, d, i, i, path);
        }
        for(int i = 0; i< n; i++){
            if(path[i])continue;
            if(d[i] > d[c])c = i;
        }
        ans += d[c];
        a++;b++;c++;
        pn(ans);
        pn(a+" "+b+" "+c);
    }
    void fill(int[][] g, int[] d, int u, int p, boolean[] path){
        for(int v:g[u]){
            if(!path[v] && p != v){
                d[v] = d[u]+1;
                fill(g, d, v, u, path);
            }

        }
    }
    int[][] makeU(int n, int[]from, int[] to){
        int[][] g = new int[n][];int[] cnt = new int[n];
        for(int i:from)cnt[i]++;
        for(int i:to)cnt[i]++;
        for(int i = 0; i< n; i++)g[i] = new int[cnt[i]];
        for(int i = 0; i< from.length; i++){
            g[from[i]][--cnt[from[i]]] = to[i];
            g[to[i]][--cnt[to[i]]] = from[i];
        }
        return g;
    }
    //SOLUTION END
    void hold(boolean b)throws Exception{if(!b)throw new Exception("Hold right there, Sparky!");}
    void exit(boolean b){if(!b)System.exit(0);}
    long IINF = (long)1e15;
    final int INF = (int)1e9+2, MX = (int)2e6+5;
    DecimalFormat df = new DecimalFormat("0.00000000000");
    double PI = 3.141592653589793238462643383279502884197169399, eps = 1e-7;
    static boolean multipleTC = false, memory = false, fileIO = false;
    FastReader in;PrintWriter out;
    void run() throws Exception{
        if(fileIO){
            in = new FastReader("");
            out = new PrintWriter("");
        }else {
            in = new FastReader();
            out = new PrintWriter(System.out);
        }
        //Solution Credits: Taranpreet Singh
        int T = (multipleTC)?ni():1;
        pre();
        for(int t = 1; t<= T; t++)solve(t);
        out.flush();
        out.close();
    }
    public static void main(String[] args) throws Exception{
        if(memory)new Thread(null, new Runnable() {public void run(){try{new Main().run();}catch(Exception e){e.printStackTrace();}}}, "1", 1 << 28).start();
        else new Main().run();
    }
    int find(int[] set, int u){return set[u] = (set[u] == u?u:find(set, set[u]));}
    int digit(long s){int ans = 0;while(s>0){s/=10;ans++;}return ans;}
    long gcd(long a, long b){return (b==0)?a:gcd(b,a%b);}
    int gcd(int a, int b){return (b==0)?a:gcd(b,a%b);}
    int bit(long n){return (n==0)?0:(1+bit(n&(n-1)));}
    void p(Object o){out.print(o);}
    void pn(Object o){out.println(o);}
    void pni(Object o){out.println(o);out.flush();}
    String n()throws Exception{return in.next();}
    String nln()throws Exception{return in.nextLine();}
    int ni()throws Exception{return Integer.parseInt(in.next());}
    long nl()throws Exception{return Long.parseLong(in.next());}
    double nd()throws Exception{return Double.parseDouble(in.next());}

    class FastReader{
        BufferedReader br;
        StringTokenizer st;
        public FastReader(){
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        public FastReader(String s) throws Exception{
            br = new BufferedReader(new FileReader(s));
        }

        String next() throws Exception{
            while (st == null || !st.hasMoreElements()){
                try{
                    st = new StringTokenizer(br.readLine());
                }catch (IOException  e){
                    throw new Exception(e.toString());
                }
            }
            return st.nextToken();
        }

        String nextLine() throws Exception{
            String str = "";
            try{
                str = br.readLine();
            }catch (IOException e){
                throw new Exception(e.toString());
            }
            return str;
        }
    }
}