Pair sort

# def pair_sort(m):
#     n = len(m)

#     positions = {}
#     for idx, val in enumerate(m):
#         if val not in positions:
#             positions[val] = []
#         positions[val].append(idx)

#     swap_count = 0
#     i = 0
#     swaps = []
#     used = [False] * n

#     while i < n - 1:
#         if used[i]:
#             i += 1
#             continue

#         if m[i] == m[i + 1] and not used[i + 1]:
#             used[i] = used[i + 1] = True
#             i += 2
#             continue

#         target = m[i]

#         for pos in positions[target]:
#             if pos > i + 1 and not used[pos]:
#                 m[i + 1], m[pos] = m[pos], m[i + 1]
#                 swaps.append((i + 1, pos))
#                 swap_count += 1
#                 used[i] = used[i + 1] = True
#                 break
#         i += 2

#     return swap_count, swaps

# n = int(input())
# m = list(map(int,input().split()))
# count, swaps = pair_sort(m)

# print(count)
# for swap in swaps:
#     print(f"{swap[0]+1} {swap[1]+1}")



# print(*m)

def pair_sort(m):
    n = len(m)
    swap_count = 0
    i = 0
    swaps = []

    while i < n - 2:
        x = m[i]
        if x == m[i+1]:
            i+=2
            break
        j = i + 2
        while j < n:
            if (m[j] == x):
                m[i + 1], m[j] = m[j], m[i + 1]
                swaps.append((x,j))
                swap_count += 1
                i += 2
                break
            j += 1

    return swap_count, swaps

n = int(input())
m = list(map(int,input().split()))
count, swaps = pair_sort(m)

print(count)
for swap in swaps:
    print(f'{swap[0]} {swap[1]}')

# print(*m)

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

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