Python script to compute big-digit values.

calc_big_digits.py

#! /usr/local/bin/python3.6
"""
Computation of big-digit values
"""
import sys
import traceback


class CalcBigDigits:
    N = 5

    def __init__(self):
        # a, b: for addition, subtraction
        # c, d: for multiplication, division
        self.a = [56789012,34567890,12345678,90123456,78901234]
        self.b = [12345678,90123456,78901234,56789012,34567890]
        self.c = [      12,34567890,12345678,90123456,78901234]
        self.d = 99

    def compute(self):
        """ Computation of big-digit values """
        try:
            self.__long_add()  # long + long
            self.__long_sub()  # long - long
            self.__long_mul()  # long * short
            self.__long_div()  # long / short
        except Exception as e:
            raise

    def __long_add(self):
        """ Computation of long + long """
        try:
            z = [0 for _ in range(self.N)]
            carry = 0
            for i in reversed(range(self.N)):
                z[i] = self.a[i] + self.b[i] + carry
                if z[i] < 100000000:
                    carry = 0
                else:
                    z[i] = z[i] - 100000000
                    carry = 1
            print(" ", end="")
            self.__display_l(self.a)
            print("+", end="")
            self.__display_l(self.b)
            print("=", end="")
            self.__display_l(z)
            print()
        except Exception as e:
            raise

    def __long_sub(self):
        """ Computation of long - long """
        try:
            z = [0 for _ in range(self.N)]
            borrow = 0
            for i in reversed(range(self.N)):
                z[i] = self.a[i] - self.b[i] - borrow
                if z[i] >= 0:
                    borrow = 0
                else:
                    z[i] += 100000000
                    borrow = 1
            print(" ", end="")
            self.__display_l(self.a)
            print("-", end="")
            self.__display_l(self.b)
            print("=", end="")
            self.__display_l(z)
            print()
        except Exception as e:
            raise

    def __long_mul(self):
        """ Computation of long * short """
        try:
            z = [0 for _ in range(self.N)]
            carry = 0
            for i in reversed(range(self.N)):
                w = self.c[i]
                z[i] = (w * self.d + carry) % 100000000
                carry = int((w * self.d + carry) / 100000000)
            print(" ", end="")
            self.__display_l(self.c)
            print("*", end="")
            self.__display_s(self.d)
            print("=", end="")
            self.__display_l(z)
            print()
        except Exception as e:
            raise

    def __long_div(self):
        """ Computation of long / short """
        try:
            z = [0 for _ in range(self.N)]
            remainder = 0
            for i in range(self.N):
                w = self.c[i]
                z[i] = int((w + remainder) / self.d)
                remainder = ((w + remainder) % self.d) * 100000000
            print(" ", end="")
            self.__display_l(self.c)
            print("/", end="")
            self.__display_s(self.d)
            print("=", end="")
            self.__display_l(z)
            print()
        except Exception as e:
            raise

    def __display_l(self, s):
        """ Display for a long value

        :param int s
        """
        try:
            for i in range(self.N):
                print(" {:08d}".format(s[i]), end="")
            print()
        except Exception as e:
            raise

    def __display_s(self, s):
        """ Display for a short value

        :param int s
        """
        try:
            for _ in range(self.N - 1):
                print(" " * 9, end="")
            print(" {:08d}".format(s))
        except Exception as e:
            raise


if __name__ == '__main__':
    try:
        obj = CalcBigDigits()
        obj.compute()
    except Exception as e:
        traceback.print_exc()
        sys.exit(1)