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:
//package round100;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Comparator;
import java.util.PriorityQueue;
import java.util.Queue;

public class C {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		int n = ni();
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		int[] imap = shrinkX(a);
		int[][] ct = new int[n][2];
		int im = imap.length;
		for(int i = 0;i < n;i++){
			ct[a[i]][0]++;
		}
		for(int i = 0;i < im;i++){
			ct[i][1] = imap[i];
		}
		Queue<int[]> q = new PriorityQueue<int[]>(n, 
			new Comparator<int[]>() {
			public int compare(int[] a, int[] b) {
				return -(a[0] - b[0]);
			}
		});
		for(int i = 0;i < im;i++)q.add(ct[i]);
		
		StringBuilder sb = new StringBuilder();
		int c = 0;
		while(q.size() >= 3){
			int[][] x = {q.poll(), q.poll(), q.poll()};
			Arrays.sort(x, new Comparator<int[]>() {
				public int compare(int[] a, int[] b) {
					return -(a[1] - b[1]);
				}
			});
			sb.append(x[0][1] + " " + x[1][1] + " " + x[2][1] + "\n");
			c++;
			for(int i = 0;i < 3;i++){
				x[i][0]--;
				if(x[i][0] > 0)q.add(x[i]);
			}
		}
		out.println(c);
		out.print(sb);
	}
	
	public static int[] shrinkX(int[] a)
	{
		int n = a.length;
		long[] b = new long[n];
		for(int i = 0;i < n;i++)b[i] = (long)a[i]<<32|i;
		Arrays.sort(b);
		int[] ret = new int[n];
		int p = 0;
		ret[0] = (int)(b[0]>>32);
		for(int i = 0;i < n;i++) {
			if(i>0 && (b[i]^b[i-1])>>32!=0) {
				p++;
				ret[p] = (int)(b[i]>>32);
			}
			a[(int)b[i]] = p;
		}
		return Arrays.copyOf(ret, p+1);
	}
	
	void run() throws Exception
	{
		is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);
		
		long s = System.currentTimeMillis();
		solve();
		out.flush();
		tr(System.currentTimeMillis()-s+"ms");
	}
	
	public static void main(String[] args) throws Exception
	{
		new C().run();
	}
	
	public int ni()
	{
		try {
			int num = 0;
			boolean minus = false;
			while((num = is.read()) != -1 && !((num >= '0' && num <= '9') || num == '-'));
			if(num == '-'){
				num = 0;
				minus = true;
			}else{
				num -= '0';
			}
			
			while(true){
				int b = is.read();
				if(b >= '0' && b <= '9'){
					num = num * 10 + (b - '0');
				}else{
					return minus ? -num : num;
				}
			}
		} catch (IOException e) {
		}
		return -1;
	}
	
	public long nl()
	{
		try {
			long num = 0;
			boolean minus = false;
			while((num = is.read()) != -1 && !((num >= '0' && num <= '9') || num == '-'));
			if(num == '-'){
				num = 0;
				minus = true;
			}else{
				num -= '0';
			}
			
			while(true){
				int b = is.read();
				if(b >= '0' && b <= '9'){
					num = num * 10 + (b - '0');
				}else{
					return minus ? -num : num;
				}
			}
		} catch (IOException e) {
		}
		return -1;
	}
	
	public String ns()
	{
		try{
			int b = 0;
			StringBuilder sb = new StringBuilder();
			while((b = is.read()) != -1 && (b == '\r' || b == '\n' || b == ' '));
			if(b == -1)return "";
			sb.append((char)b);
			while(true){
				b = is.read();
				if(b == -1)return sb.toString();
				if(b == '\r' || b == '\n' || b == ' ')return sb.toString();
				sb.append((char)b);
			}
		} catch (IOException e) {
		}
		return "";
	}
	
	public char[] ns(int n)
	{
		char[] buf = new char[n];
		try{
			int b = 0, p = 0;
			while((b = is.read()) != -1 && (b == ' ' || b == '\r' || b == '\n'));
			if(b == -1)return null;
			buf[p++] = (char)b;
			while(p < n){
				b = is.read();
				if(b == -1 || b == ' ' || b == '\r' || b == '\n')break;
				buf[p++] = (char)b;
			}
			return Arrays.copyOf(buf, p);
		} catch (IOException e) {
		}
		return null;
	}
	
	
	double nd() { return Double.parseDouble(ns()); }
	boolean oj = System.getProperty("ONLINE_JUDGE") != null;
	void tr(Object... o) { if(!oj)System.out.println(Arrays.deepToString(o)); }
}