description: Christmas is coming, Icy has just received a box of chocolates from her grandparents! The box contains n chocolates. The i-th chocolate has a non-negative integer type a_i.
  
  Icy believes that good things come in pairs. Unfortunately, all types of chocolates are distinct (all a_i are distinct). Icy wants to make at least one pair of chocolates the same type. 
  
  As a result, she asks her grandparents to perform some chocolate exchanges. Before performing any chocolate exchanges, Icy chooses two chocolates with indices x and y (1 ≤ x, y ≤ n, x ≠ y).
  
  In a chocolate exchange, Icy's grandparents choose a non-negative integer k, such that 2^k ≥ a_x, and change the type of the chocolate x from a_x to 2^k - a_x (that is, perform a_x := 2^k - a_x).
  
  The chocolate exchanges will be stopped only when a_x = a_y. Note that other pairs of equal chocolate types do not stop the procedure.
  
  Icy's grandparents are smart, so they would choose the sequence of chocolate exchanges that minimizes the number of exchanges needed. Since Icy likes causing trouble, she wants to maximize the minimum number of exchanges needed by choosing x and y appropriately. She wonders what is the optimal pair (x, y) such that the minimum number of exchanges needed is maximized across all possible choices of (x, y).
  
  Since Icy is not good at math, she hopes that you can help her solve the problem.
  
  Input
  
  The first line of the input contains a single integer n (2 ≤ n ≤ 2 ⋅ 10^5) — the number of chocolates.
  
  The second line of the input contains n integers a_1, a_2, ..., a_n (0 ≤ a_i ≤ 10^9).
  
  It is guaranteed that all a_i are distinct.
  
  Output
  
  Output three integers x, y, and m.
  
  x and y are indices of the optimal chocolates to perform exchanges on. Your output must satisfy 1 ≤ x, y ≤ n, x ≠ y.
  
  m is the number of exchanges needed to obtain a_x = a_y. We can show that m ≤ 10^9 for any pair of chocolates.
  
  If there are multiple solutions, output any.
  
  Examples
  
  Input
  
  
  5
  5 6 7 8 9
  
  
  Output
  
  
  2 5 5
  
  
  Input
  
  
  2
  4 8
  
  
  Output
  
  
  1 2 2
  
  Note
  
  In the first test case, the minimum number of exchanges needed to exchange a chocolate of type 6 to a chocolate of type 9 is 5. The sequence of exchanges is as follows: 6 → 2 → 0 → 1 → 7 → 9.
  
  In the second test case, the minimum number of exchanges needed to exchange a chocolate of type 4 to a chocolate of type 8 is 2. The sequence of exchanges is as follows: 4 → 0 → 8.
solution: //package round761;
  import java.io.*;
  import java.util.*;
  
  public class E {
  	InputStream is;
  	FastWriter out;
  	String INPUT = "";
  	
  	void solve()
  	{
  		int n = ni();
  		int[] a = na(n);
  
  		TrieArrayByLink trie = new TrieArrayByLink(30*n);
  		int[] b = new int[31];
  		for(int i = 0;i < n;i++){
  			if(a[i] == 0){
  				trie.add(new int[0], i);
  				continue;
  			}
  			int p = 0;
  			for(int j = 0;j < 30;j++){
  				if(a[i]<<~j<0){
  //					b[p++] = j;
  					b[p++] = j+1;
  					for(int k = j+1;k < 30;k++){
  						if((a[i]>>>k&1) != (a[i]>>>k+1&1)){
  							b[p++] = k+1;
  						}
  					}
  //					tr(Arrays.copyOf(b, p));
  					trie.add(Arrays.copyOf(b, p), i);
  					break;
  				}
  			}
  		}
  		trie.dfs(0);
  		out.println(trie.argx+1 +" " + (trie.argy+1) + " " + trie.ans);
  	}
  
  	public static class TrieArrayByLink {
  		// root = 0
  		public int[] next;
  		public int[] firstChild;
  		public int[] cs;
  		public int gen;
  		public int size;
  
  		public int[] hit;
  
  		public TrieArrayByLink(int n)
  		{
  			this.size = n;
  			this.next = new int[n];
  			this.firstChild = new int[n];
  			this.cs = new int[n];
  			this.hit = new int[n];
  			Arrays.fill(this.hit, -1);
  			this.gen = 1;
  
  			Arrays.fill(this.next, -1);
  			Arrays.fill(this.firstChild, -1);
  			Arrays.fill(this.cs, (char)0);
  		}
  
  		public void add(int[] s, int id)
  		{
  			int cur = 0;
  			for(int c : s){
  				int nex = firstChild[cur];
  				if(nex == -1){
  					// if first child
  					cs[gen] = c;
  					nex = firstChild[cur] = gen;
  					gen++;
  				}else{
  					// if sibling
  					for(;nex != -1 && cs[nex] != c; nex = next[nex]);
  					if(nex == -1){
  						cs[gen] = c;
  						int oldfc = firstChild[cur];
  						nex = firstChild[cur] = gen;
  						next[nex] = oldfc;
  						gen++;
  					}
  				}
  				cur = nex;
  			}
  			hit[cur] = id;
  		}
  
  		int ans = 0;
  		int argx = -1, argy = -1;
  
  		public int[] dfs(int cur)
  		{
  			int[] best = null;
  			int[] best2 = null;
  			if(hit[cur] != -1){
  				best = new int[]{0, hit[cur]};
  			}
  			for(int nex = firstChild[cur];nex != -1; nex = next[nex]){
  				int[] res = dfs(nex);
  				if(best == null || res[0] > best[0]){
  					best2 = best;
  					best = res;
  				}else if(best2 == null || res[0] > best2[0]){
  					best2 = res;
  				}
  			}
  			if(best2 != null && best[0] + best2[0] > ans){
  				ans = best[0] + best2[0];
  				argx = best[1];
  				argy = best2[1];
  			}
  			best[0]++;
  			return best;
  		}
  	}
  
  
  
  	void run() throws Exception
  	{
  //		int n = 200000, m = 99999;
  //		Random gen = new Random();
  //		StringBuilder sb = new StringBuilder();
  //		sb.append(n + " ");
  //		for (int i = 0; i < n; i++) {
  //			sb.append(gen.nextInt(1000000000)+1 + " ");
  //		}
  //		INPUT = sb.toString();
  
  
  		is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
  		out = new FastWriter(System.out);
  		
  		long s = System.currentTimeMillis();
  		solve();
  		out.flush();
  		tr(System.currentTimeMillis()-s+"ms");
  	}
  	
  	public static void main(String[] args) throws Exception { new E().run(); }
  	
  	private byte[] inbuf = new byte[1024];
  	public int lenbuf = 0, ptrbuf = 0;
  	
  	private int readByte()
  	{
  		if(lenbuf == -1)throw new InputMismatchException();
  		if(ptrbuf >= lenbuf){
  			ptrbuf = 0;
  			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
  			if(lenbuf <= 0)return -1;
  		}
  		return inbuf[ptrbuf++];
  	}
  	
  	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
  	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
  	
  	private double nd() { return Double.parseDouble(ns()); }
  	private char nc() { return (char)skip(); }
  	
  	private String ns()
  	{
  		int b = skip();
  		StringBuilder sb = new StringBuilder();
  		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
  			sb.appendCodePoint(b);
  			b = readByte();
  		}
  		return sb.toString();
  	}
  	
  	private char[] ns(int n)
  	{
  		char[] buf = new char[n];
  		int b = skip(), p = 0;
  		while(p < n && !(isSpaceChar(b))){
  			buf[p++] = (char)b;
  			b = readByte();
  		}
  		return n == p ? buf : Arrays.copyOf(buf, p);
  	}
  
  	private int[] na(int n)
  	{
  		int[] a = new int[n];
  		for(int i = 0;i < n;i++)a[i] = ni();
  		return a;
  	}
  
  	private long[] nal(int n)
  	{
  		long[] a = new long[n];
  		for(int i = 0;i < n;i++)a[i] = nl();
  		return a;
  	}
  
  	private char[][] nm(int n, int m) {
  		char[][] map = new char[n][];
  		for(int i = 0;i < n;i++)map[i] = ns(m);
  		return map;
  	}
  
  	private int[][] nmi(int n, int m) {
  		int[][] map = new int[n][];
  		for(int i = 0;i < n;i++)map[i] = na(m);
  		return map;
  	}
  
  	private int ni() { return (int)nl(); }
  
  	private long nl()
  	{
  		long num = 0;
  		int b;
  		boolean minus = false;
  		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
  		if(b == '-'){
  			minus = true;
  			b = readByte();
  		}
  
  		while(true){
  			if(b >= '0' && b <= '9'){
  				num = num * 10 + (b - '0');
  			}else{
  				return minus ? -num : num;
  			}
  			b = readByte();
  		}
  	}
  
  	public static class FastWriter
  	{
  		private static final int BUF_SIZE = 1<<13;
  		private final byte[] buf = new byte[BUF_SIZE];
  		private final OutputStream out;
  		private int ptr = 0;
  
  		private FastWriter(){out = null;}
  
  		public FastWriter(OutputStream os)
  		{
  			this.out = os;
  		}
  
  		public FastWriter(String path)
  		{
  			try {
  				this.out = new FileOutputStream(path);
  			} catch (FileNotFoundException e) {
  				throw new RuntimeException("FastWriter");
  			}
  		}
  
  		public FastWriter write(byte b)
  		{
  			buf[ptr++] = b;
  			if(ptr == BUF_SIZE)innerflush();
  			return this;
  		}
  
  		public FastWriter write(char c)
  		{
  			return write((byte)c);
  		}
  
  		public FastWriter write(char[] s)
  		{
  			for(char c : s){
  				buf[ptr++] = (byte)c;
  				if(ptr == BUF_SIZE)innerflush();
  			}
  			return this;
  		}
  
  		public FastWriter write(String s)
  		{
  			s.chars().forEach(c -> {
  				buf[ptr++] = (byte)c;
  				if(ptr == BUF_SIZE)innerflush();
  			});
  			return this;
  		}
  
  		private static int countDigits(int l) {
  			if (l >= 1000000000) return 10;
  			if (l >= 100000000) return 9;
  			if (l >= 10000000) return 8;
  			if (l >= 1000000) return 7;
  			if (l >= 100000) return 6;
  			if (l >= 10000) return 5;
  			if (l >= 1000) return 4;
  			if (l >= 100) return 3;
  			if (l >= 10) return 2;
  			return 1;
  		}
  
  		public FastWriter write(int x)
  		{
  			if(x == Integer.MIN_VALUE){
  				return write((long)x);
  			}
  			if(ptr + 12 >= BUF_SIZE)innerflush();
  			if(x < 0){
  				write((byte)'-');
  				x = -x;
  			}
  			int d = countDigits(x);
  			for(int i = ptr + d - 1;i >= ptr;i--){
  				buf[i] = (byte)('0'+x%10);
  				x /= 10;
  			}
  			ptr += d;
  			return this;
  		}
  
  		private static int countDigits(long l) {
  			if (l >= 1000000000000000000L) return 19;
  			if (l >= 100000000000000000L) return 18;
  			if (l >= 10000000000000000L) return 17;
  			if (l >= 1000000000000000L) return 16;
  			if (l >= 100000000000000L) return 15;
  			if (l >= 10000000000000L) return 14;
  			if (l >= 1000000000000L) return 13;
  			if (l >= 100000000000L) return 12;
  			if (l >= 10000000000L) return 11;
  			if (l >= 1000000000L) return 10;
  			if (l >= 100000000L) return 9;
  			if (l >= 10000000L) return 8;
  			if (l >= 1000000L) return 7;
  			if (l >= 100000L) return 6;
  			if (l >= 10000L) return 5;
  			if (l >= 1000L) return 4;
  			if (l >= 100L) return 3;
  			if (l >= 10L) return 2;
  			return 1;
  		}
  
  		public FastWriter write(long x)
  		{
  			if(x == Long.MIN_VALUE){
  				return write("" + x);
  			}
  			if(ptr + 21 >= BUF_SIZE)innerflush();
  			if(x < 0){
  				write((byte)'-');
  				x = -x;
  			}
  			int d = countDigits(x);
  			for(int i = ptr + d - 1;i >= ptr;i--){
  				buf[i] = (byte)('0'+x%10);
  				x /= 10;
  			}
  			ptr += d;
  			return this;
  		}
  
  		public FastWriter write(double x, int precision)
  		{
  			if(x < 0){
  				write('-');
  				x = -x;
  			}
  			x += Math.pow(10, -precision)/2;
  			//		if(x < 0){ x = 0; }
  			write((long)x).write(".");
  			x -= (long)x;
  			for(int i = 0;i < precision;i++){
  				x *= 10;
  				write((char)('0'+(int)x));
  				x -= (int)x;
  			}
  			return this;
  		}
  
  		public FastWriter writeln(char c){
  			return write(c).writeln();
  		}
  
  		public FastWriter writeln(int x){
  			return write(x).writeln();
  		}
  
  		public FastWriter writeln(long x){
  			return write(x).writeln();
  		}
  
  		public FastWriter writeln(double x, int precision){
  			return write(x, precision).writeln();
  		}
  
  		public FastWriter write(int... xs)
  		{
  			boolean first = true;
  			for(int x : xs) {
  				if (!first) write(' ');
  				first = false;
  				write(x);
  			}
  			return this;
  		}
  
  		public FastWriter write(long... xs)
  		{
  			boolean first = true;
  			for(long x : xs) {
  				if (!first) write(' ');
  				first = false;
  				write(x);
  			}
  			return this;
  		}
  
  		public FastWriter writeln()
  		{
  			return write((byte)'\n');
  		}
  
  		public FastWriter writeln(int... xs)
  		{
  			return write(xs).writeln();
  		}
  
  		public FastWriter writeln(long... xs)
  		{
  			return write(xs).writeln();
  		}
  
  		public FastWriter writeln(char[] line)
  		{
  			return write(line).writeln();
  		}
  
  		public FastWriter writeln(char[]... map)
  		{
  			for(char[] line : map)write(line).writeln();
  			return this;
  		}
  
  		public FastWriter writeln(String s)
  		{
  			return write(s).writeln();
  		}
  
  		private void innerflush()
  		{
  			try {
  				out.write(buf, 0, ptr);
  				ptr = 0;
  			} catch (IOException e) {
  				throw new RuntimeException("innerflush");
  			}
  		}
  
  		public void flush()
  		{
  			innerflush();
  			try {
  				out.flush();
  			} catch (IOException e) {
  				throw new RuntimeException("flush");
  			}
  		}
  
  		public FastWriter print(byte b) { return write(b); }
  		public FastWriter print(char c) { return write(c); }
  		public FastWriter print(char[] s) { return write(s); }
  		public FastWriter print(String s) { return write(s); }
  		public FastWriter print(int x) { return write(x); }
  		public FastWriter print(long x) { return write(x); }
  		public FastWriter print(double x, int precision) { return write(x, precision); }
  		public FastWriter println(char c){ return writeln(c); }
  		public FastWriter println(int x){ return writeln(x); }
  		public FastWriter println(long x){ return writeln(x); }
  		public FastWriter println(double x, int precision){ return writeln(x, precision); }
  		public FastWriter print(int... xs) { return write(xs); }
  		public FastWriter print(long... xs) { return write(xs); }
  		public FastWriter println(int... xs) { return writeln(xs); }
  		public FastWriter println(long... xs) { return writeln(xs); }
  		public FastWriter println(char[] line) { return writeln(line); }
  		public FastWriter println(char[]... map) { return writeln(map); }
  		public FastWriter println(String s) { return writeln(s); }
  		public FastWriter println() { return writeln(); }
  	}
  
  	public void trnz(int... o)
  	{
  		for(int i = 0;i < o.length;i++)if(o[i] != 0)System.out.print(i+":"+o[i]+" ");
  		System.out.println();
  	}
  
  	// print ids which are 1
  	public void trt(long... o)
  	{
  		Queue<Integer> stands = new ArrayDeque<>();
  		for(int i = 0;i < o.length;i++){
  			for(long x = o[i];x != 0;x &= x-1)stands.add(i<<6|Long.numberOfTrailingZeros(x));
  		}
  		System.out.println(stands);
  	}
  
  	public void tf(boolean... r)
  	{
  		for(boolean x : r)System.out.print(x?'#':'.');
  		System.out.println();
  	}
  
  	public void tf(boolean[]... b)
  	{
  		for(boolean[] r : b) {
  			for(boolean x : r)System.out.print(x?'#':'.');
  			System.out.println();
  		}
  		System.out.println();
  	}
  
  	public void tf(long[]... b)
  	{
  		if(INPUT.length() != 0) {
  			for (long[] r : b) {
  				for (long x : r) {
  					for (int i = 0; i < 64; i++) {
  						System.out.print(x << ~i < 0 ? '#' : '.');
  					}
  				}
  				System.out.println();
  			}
  			System.out.println();
  		}
  	}
  
  	public void tf(long... b)
  	{
  		if(INPUT.length() != 0) {
  			for (long x : b) {
  				for (int i = 0; i < 64; i++) {
  					System.out.print(x << ~i < 0 ? '#' : '.');
  				}
  			}
  			System.out.println();
  		}
  	}
  
  	private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
  	private void tr(Object... o) { if(!oj)System.out.println(Arrays.deepToString(o)); }
  }
  