Problem: You have an array a_1, a_2, ..., a_n where a_i = i.

In one step, you can choose two indices x and y (x ≠ y) and set a_x = \left⌈ (a_x)/(a_y) \right⌉ (ceiling function).

Your goal is to make array a consist of n - 1 ones and 1 two in no more than n + 5 steps. Note that you don't have to minimize the number of steps.

Input

The first line contains a single integer t (1 ≤ t ≤ 1000) — the number of test cases.

The first and only line of each test case contains the single integer n (3 ≤ n ≤ 2 ⋅ 10^5) — the length of array a.

It's guaranteed that the sum of n over test cases doesn't exceed 2 ⋅ 10^5.

Output

For each test case, print the sequence of operations that will make a as n - 1 ones and 1 two in the following format: firstly, print one integer m (m ≤ n + 5) — the number of operations; next print m pairs of integers x and y (1 ≤ x, y ≤ n; x ≠ y) (x may be greater or less than y) — the indices of the corresponding operation.

It can be proven that for the given constraints it's always possible to find a correct sequence of operations.

Example

Input


2
3
4


Output


2
3 2
3 2
3
3 4
4 2
4 2

Note

In the first test case, you have array a = [1, 2, 3]. For example, you can do the following: 

  1. choose 3, 2: a_3 = \left⌈ (a_3)/(a_2) \right⌉ = 2 and array a = [1, 2, 2]; 
  2. choose 3, 2: a_3 = \left⌈ 2/2 \right⌉ = 1 and array a = [1, 2, 1]. 

You've got array with 2 ones and 1 two in 2 steps.

In the second test case, a = [1, 2, 3, 4]. For example, you can do the following: 

  1. choose 3, 4: a_3 = \left⌈ 3/4 \right⌉ = 1 and array a = [1, 2, 1, 4]; 
  2. choose 4, 2: a_4 = \left⌈ 4/2 \right⌉ = 2 and array a = [1, 2, 1, 2]; 
  3. choose 4, 2: a_4 = \left⌈ 2/2 \right⌉ = 1 and array a = [1, 2, 1, 1]. 

Solution (in JAVA):

Solution:
import java.awt.*;
import java.io.*;
import java.util.*;
import java.util.List;
import java.util.concurrent.LinkedBlockingQueue;

public class Coding {

    private static BufferedReader bi = new BufferedReader(new InputStreamReader(System.in));
    private static BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(System.out));

    public static void main(String[] args) {
        try {
            run();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void run() throws Exception {
        InputModule inp = new InputModule();
        OutputModule out = new OutputModule();
        int t = inp.cinInt();
        while (t > 0) {
            List<Point> ops = new ArrayList<>();
            int n = inp.cinInt();
            for(int i=3;i<=n-1;++i) {
                if (i==8) continue;
                else {
                    ops.add(new Point(i, n));
                }
            }
            if (n>8) {
                int val = n;
                while (val!=1) {
                    ops.add(new Point(n, 8));
                    val = (val/8) + ((val%8==0)?0:1);
                }

                ops.add(new Point(8, 2));
                ops.add(new Point(8, 2));
                ops.add(new Point(8, 2));

            } else {
                int val = n;
                while (val!=1) {
                    ops.add(new Point(n, 2));
                    val = (val/2) + ((val%2==0)?0:1);
                }
            }

            out.printInt(ops.size());
            out.printPoints(ops);
            t--;
        }
    }

    private static class InputModule {
        private int cinInt() throws Exception {
            return Integer.parseInt(bi.readLine().split(" ")[0].trim());
        }

        private long cinLong() throws Exception {
            return Long.parseLong(bi.readLine().split(" ")[0].trim());
        }

        private Double cinDouble() throws Exception {
            return Double.parseDouble(bi.readLine().split(" ")[0].trim());
        }

        private String cinString() throws Exception {
            return bi.readLine();
        }

        private int[] cinIntArray(int n) throws Exception {
            String input = bi.readLine();
            String[] values = input.split(" ");
            int[] ar = new int[n];
            for (int i = 0; i < n; ++i) {
                ar[i] = Integer.parseInt(values[i]);
            }
            return ar;
        }

        private int[] cinIntArray() throws Exception {
            String input = bi.readLine();
            String[] values = input.split(" ");
            int[] ar = new int[values.length];
            for (int i = 0; i < values.length; ++i) {
                ar[i] = Integer.parseInt(values[i]);
            }
            return ar;
        }

        private long[] cinLongArray(int n) throws Exception {
            String input = bi.readLine();
            String[] values = input.split(" ");
            long[] ar = new long[n];
            for (int i = 0; i < n; ++i) {
                ar[i] = Long.parseLong(values[i]);
            }
            return ar;
        }

        private String[] cinStringArray(int n) throws Exception {
            return bi.readLine().split(" ");
        }
    }

    private static class OutputModule {
        private void printInt(int ans) throws Exception {
            writer.append(ans + "\n");
            writer.flush();
        }

        private void printLong(long ans) throws Exception {
            writer.append(ans + "\n");
            writer.flush();
        }

        private void printDouble(Double ans) throws Exception {
            writer.append(String.format("%.10f", ans));
            writer.append("\n");
            writer.flush();
        }

        private void printString(String ans) throws Exception {
            writer.append(ans + "\n");
            writer.flush();
        }

        private void printIntArray(int[] ans) throws Exception {
            for (int i = 0; i < ans.length; ++i) {
                writer.append(ans[i] + " ");
            }
            writer.append("\n");
            writer.flush();
        }

        private void printLongArray(long[] ans) throws Exception {
            for (int i = 0; i < ans.length; ++i) {
                writer.append(ans[i] + " ");
            }
            writer.append("\n");
            writer.flush();
        }

        private void printIntMatrix(int[][] mat, int n, int m) throws Exception {
            for (int i = 0; i < n; ++i) {
                for (int j = 0; j < m; ++j) {
                    writer.append(mat[i][j] + " ");
                }
                writer.append("\n");
            }
            writer.flush();
        }

        private void printLongMatrix(long[][] mat, int n, int m) throws Exception {
            for (int i = 0; i < n; ++i) {
                for (int j = 0; j < m; ++j) {
                    writer.append(mat[i][j] + " ");
                }
                writer.append("\n");
            }
            writer.flush();
        }

        private void printPoint(Point p) throws Exception {
            writer.append(p.x + " " + p.y + "\n");
            writer.flush();
        }

        private void printPoints(List<Point> p) throws Exception {
            for (Point pp : p) {
                writer.append(pp.x + " " + pp.y + "\n");
            }
            writer.flush();
        }
    }
}