Problem: As meticulous Gerald sets the table and caring Alexander sends the postcards, Sergey makes snowmen. Each showman should consist of three snowballs: a big one, a medium one and a small one. Sergey's twins help him: they've already made n snowballs with radii equal to r1, r2, ..., rn. To make a snowman, one needs any three snowballs whose radii are pairwise different. For example, the balls with radii 1, 2 and 3 can be used to make a snowman but 2, 2, 3 or 2, 2, 2 cannot. Help Sergey and his twins to determine what maximum number of snowmen they can make from those snowballs.

Input

The first line contains integer n (1 ≤ n ≤ 105) — the number of snowballs. The next line contains n integers — the balls' radii r1, r2, ..., rn (1 ≤ ri ≤ 109). The balls' radii can coincide.

Output

Print on the first line a single number k — the maximum number of the snowmen. Next k lines should contain the snowmen's descriptions. The description of each snowman should consist of three space-separated numbers — the big ball's radius, the medium ball's radius and the small ball's radius. It is allowed to print the snowmen in any order. If there are several solutions, print any of them.

Examples

Input

7
1 2 3 4 5 6 7


Output

2
3 2 1
6 5 4


Input

3
2 2 3


Output

0

Solution (in JAVA):

Solution:


import java.awt.Point;
import java.io.*;
import java.math.BigInteger;
import java.util.*;
import java.util.Map.Entry;

import static java.lang.Math.*;

public class C implements Runnable{
    
    final boolean ONLINE_JUDGE = System.getProperty("ONLINE_JUDGE") != null;
    
    BufferedReader in;
    PrintWriter out;
    StringTokenizer tok = new StringTokenizer("");
    
    void init() throws FileNotFoundException{
        if (ONLINE_JUDGE){
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);
        }else{
            in = new BufferedReader(new FileReader("input.txt"));
            out = new PrintWriter("output.txt");
        }
    }
    
    String readString() throws IOException{
        while(!tok.hasMoreTokens()){
            try{
                tok = new StringTokenizer(in.readLine());
            }catch (Exception e){
                return null;
            }
        }
        return tok.nextToken();
    }
    
    int readInt() throws IOException{
        return Integer.parseInt(readString());
    }
    
    long readLong() throws IOException{
        return Long.parseLong(readString());
    }
    
    double readDouble() throws IOException{
        return Double.parseDouble(readString());
    }
    
    public static void main(String[] args){
        new Thread(null, new C(), "", 256 * (1L << 20)).start();
    }
    
    long timeBegin, timeEnd;

    void timePrint(){
        timeEnd = System.currentTimeMillis();
        System.err.println("Time = " + (timeEnd - timeBegin));
    }
    
    long memoryTotal, memoryFree;
    

    void memoryPrint(){
        memoryFree = Runtime.getRuntime().freeMemory();
        System.err.println("Memory = " + ((memoryTotal - memoryFree) >> 10) + " KB");
    }
    
    boolean DEBUG = false;
    
    void debugPrint(Object... objects){
        if (DEBUG){
            for (Object o: objects){
                System.err.println(o.toString());
            }
        }
    }
    
    public void run(){
        try{
            timeBegin = System.currentTimeMillis();
            memoryTotal = Runtime.getRuntime().totalMemory();
            init();
            solve();
            out.close();
            timePrint();
            memoryPrint();
        }catch (Exception e){
            e.printStackTrace(System.err);
            System.exit(-1);
        }
    }
    
    class CmpX implements Comparator<Point>{

        @Override
        public int compare(Point p1, Point p2) {
            return p2.x - p1.x;
        }
        
    }
    
    class CmpY implements Comparator<Point>{

        @Override
        public int compare(Point p1, Point p2) {
            return p2.y - p1.y;
        }
        
    }
    
    void solve() throws IOException{
        int n = readInt();
        
        HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();
        
        for (int i = 0; i < n; i++){
            int r = readInt();
            
            if (!map.containsKey(r)){
                map.put(r, 1);
            }else{
                map.put(r, map.get(r) + 1);
            }
        } 
        
        CmpX cmpX = new CmpX();
        CmpY cmpY = new CmpY();
        
        PriorityQueue<Point> q = new PriorityQueue<Point>(map.size(), cmpY);
        
        for (Entry e: map.entrySet()){
            q.add(new Point((Integer) e.getKey(), (Integer) e.getValue()));
        }
        
        int res = 0;
        
        Point[] p = new Point[3];
        
        int[][] a = new int[n][3];
        
        while (q.size() >= 3){
            for (int i = 0; i < 3; i++){
                p[i] = q.poll();
            }
            
            Arrays.sort(p, cmpX);
            
            for (int i = 0; i < 3; i++){
                a[res][i] = p[i].x;
                
                p[i].y--;
                if (p[i].y > 0) q.add(p[i]);
            }
            
            res++;
        }
        
        out.println(res);
        
        for (int i = 0; i < res; i++){
            for (int r: a[i]){
                out.print(r + " ");
            }
            
            out.println();
        }
    }
}