def solve_3_1(input_data): result = bin(input_data) firstNum = '1' newString = '' for i in result[::-1]: if i == '1': break newString = newString + i newString = firstNum + newString return newString def main(): print(solve_3_1(1000)) print(solve_3_1(10)) print(solve_3_1(9)) if __name__ == "__main__": main()