import bisect

n = int(input())
a = list(map(int, input().split()))
elements = sorted([(a[i], i + 1) for i in range(n)], key=lambda x: (x[0], x[1]))
pos = [e[1] for e in elements]

d = []
for x in pos:
    idx = bisect.bisect_left(d, x)
    if idx == len(d):
        d.append(x)
    else:
        d[idx] = x
print(n - len(d))