from collections import defaultdict


n = int(input())
numbers = list(enumerate(map(int, input().split())))
permutations = {}
positions = defaultdict(set)
for index in range(n):
    positions[numbers[index][1]].add(index)
numbers.sort(key=lambda x: x[1])
result = True
print(numbers)
print(positions)
for index in range(n):
    if numbers[index][0] == index:
        continue
    second_index = numbers[index][0]
    print(second_index, result)
    value = numbers[second_index][1]
    if index in positions[value]:
        if index > second_index:
            permutations[index] = second_index
    else:
        result = False
if result:
    print("Yes")
    print(len(permutations))
    for index, second_index in permutations.items():
        print(index + 1, second_index + 1)
else:
    print("No")