from heapq import heappush, heappop

N = int(input())
H = sorted(list(map(int, input().split())))

MAX = max(H[i].bit_length()-i-1 for i in range(N))

que = []
for h in H:
    heappush(que, -h)

cnt = MAX+N-1
for _ in range(MAX+N):
    if not que:
        break
    n = -heappop(que)
    n -= 1<<min(cnt, 60)
    cnt -= 1
    if 1 <= n:
        heappush(que, n)

print(N+MAX+1 if que else N+MAX)