def main():
    import sys
    input = sys.stdin.read().split()
    ptr = 0
    N = int(input[ptr])
    ptr += 1
    M = int(input[ptr])
    ptr += 1
    strings = []
    for _ in range(M):
        s = input[ptr].strip()
        strings.append(s)
        ptr += 1

    mask = {}
    for i in range(1, N + 1):
        pos = N - i  # 0-based index of the string
        mask_i = 0
        for m_idx in range(M):
            if strings[m_idx][pos] == '1':
                mask_i |= (1 << m_idx)
        mask[i] = mask_i

    for i in range(1, N + 1):
        for j in range(i + 1, N + 1):
            if mask[i] ^ mask[j] == 0:
                print("No")
                return

    print("Yes")

if __name__ == "__main__":
    main()