n = int(input())

A = list(map(int, input().split()))

memo = [-1] * n
for idx, a in enumerate(A):
    memo[a - 1] = idx
# print("memo", memo)

cnt = 0
used = [0] * n
dame = [0] * n
for i in range(n):
    idx = memo[i]
    if used[idx]:
        continue
    used[idx] = 1
    cnt += 1
    # print(cnt, i, idx)
    if idx - 1 >= 0:
        used[idx - 1] = 1
    # print(i, used)

print(cnt)