from collections import defaultdict


amount = int(input())
numbers = list(map(int, input().split()))
counter = defaultdict(int)
counts = defaultdict(set)
max_prefix = 0
for index in range(amount):
    old_count = counter[numbers[index]]
    new_count = old_count + 1
    counter[numbers[index]] = new_count
    if old_count:
        counts[old_count].discard(numbers[index])
        if len(counts[old_count]) == 0:
            counts.pop(old_count)
    counts[new_count].add(numbers[index])
    if len(counts) == 1 and min(counts) == 1:
        max_prefix = index
    if len(counts) == 2:
        max_count = max(counts)
        min_count = min(counts)
        if min_count == 1 and len(counts[min_count]) == 1:
            max_prefix = index
        if max_count - min_count == 1 and len(counts[max_count]) == 1:
            max_prefix = index
print(max_prefix + 1)