Pair sort

n = int(input())
numbers = [int(x) for x in input().split()]
swaps = []
index = 0

def binary_search(array, x):
    low = 0
    high = len(array)-1

    while low <= high:
        mid = (high + low) // 2
        if array[mid] < x:
            low = mid + 1
        elif array[mid] > x:
            high = mid - 1
        else:
            return mid
    
    return -1

while index < 2*n:
    if numbers[index] != numbers[index+1]:
        j = binary_search(numbers[index+2:], numbers[index]) + index + 2
        numbers[index+1], numbers[j] = numbers[j], numbers[index+1]
        swaps.append([index+1, j])

    index += 2

print(len(swaps))
for swap in swaps:
    print(swap[0]+1, swap[1]+1)

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: WRONG ANSWER