def intToBitString(a, bit = 256):
    """
    Converts an integer to a binary string representation (without '0b')
    :param a: The integer to convert (integer)
    :param bit: The size of the representation in bit (integer)
    :return: Binary string representation (String)
    """
    str = bin(a)[2:]
    return (bit-len(str))*"0" + str