import numpy as np

n = int(input())
m = int(input())
lis = [np.array([bool(int(c)) for c in input()]) for _ in [0] * m]

for i in range(n):
	a = np.array([True] * n)
	b = np.array([False] * n)
	for bits in lis:
		if(bits[i]):
			a &= bits
		else:
			b |= bits
	for j in range(n):
		if(i == j):
			continue
		if(a[j] and np.logical_not(b[j])):
			print("No")
			exit(0)
print("Yes")