N, A, B = [input() for _ in range(3)]
N = int(N)
A = A.split()
B = B.split()

def main():
	kan(N, A, B)

def kan(n, a, b):
	judge = 0
	for i in range(n):
		if int(b[i]) >= int(a[i]):
			judge += 1
	print(judge)

if __name__ == '__main__':
	main()