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 PYTHON3):

Solution:
# cook your dish here
import sys
from functools import lru_cache, cmp_to_key
from heapq import merge, heapify, heappop, heappush
from math import *
from collections import defaultdict as dd, deque, Counter as C
from itertools import combinations as comb, permutations as perm
from bisect import bisect_left as bl, bisect_right as br, bisect
from time import perf_counter
from fractions import Fraction
import copy
import time
starttime = time.time()
mod = int(pow(10, 9) + 7)
mod2 = 998244353
# from sys import stdin
# input = stdin.readline
def data(): return sys.stdin.readline().strip()
def out(*var, end="\n"): sys.stdout.write(' '.join(map(str, var))+end)
def L(): return list(sp())
def sl(): return list(ssp())
def sp(): return map(int, data().split())
def ssp(): return map(str, data().split())
def l1d(n, val=0): return [val for i in range(n)]
def l2d(n, m, val=0): return [l1d(n, val) for j in range(m)]
try:
    # sys.setrecursionlimit(int(pow(10,7)))
    sys.stdin = open("input.txt", "r")
    # sys.stdout = open("../output.txt", "w")
except:
    pass
def pmat(A):
    for ele in A:
        print(*ele,end="\n")
def seive():
    prime=[1 for i in range(10**6+1)]
    prime[0]=0
    prime[1]=0
    for i in range(10**6+1):
        if(prime[i]):
            for j in range(2*i,10**6+1,i):
                prime[j]=0
    return prime




# exit()
for term in range(L()[0]):
    n=L()[0]
    c=min(32,int(n**0.5)+1)
    A=[i for i in range(n+1)]
    ans=[]
    for i in range(3,c):
        if A[i]!=1:
            A[i]=ceil(A[i]/c)
            ans.append([i,c])
    for i in range(c+1,n):
        if A[i]!=1:
            A[i]=ceil(A[i]/n)
            ans.append([i,n])
    # print(A)
    # print(ans)
    while(A[n]!=1 and n!=2):
        A[n]=ceil(A[n]/c)
        ans.append([n,c])
    while(A[c]!=1 and c!=2):
        A[c]=ceil(A[c]/2)
        ans.append([c,2])
    print(len(ans))
    # # print(A[1:])
    for ele in ans:
        print(*ele)
    # print((len(ans)<=n+5),A.count(1),A.count(2)) 
    # if not ((len(ans)<=n+5) and A.count(1)==n-1 and A.count(2)==1):
    #     print(n)


endtime = time.time()
# print(f"Runtime of the program is {endtime - starttime}")