Example #1
0
bignum bignum_subtract(bignum& a, bignum& b)
{	
	bignum c;
	if (b.size() > a.size())
		c.push_back(0);
	else if (a.size() == b.size() && b.back() > a.back())
		c.push_back(0);
	else
	{
		int k;
		for (unsigned int i = 0; i < a.size() + b.size(); i++)
		{
			k = 0;
		
			if (i < a.size())
				k += a[i];
		
			if (i < b.size())
				k -= b[i];
	
			c.push_back(k);
		}
		
		for (unsigned int i = 0; i < c.size() - 1; i++)
		{
			while (c[i] < 0)
			{
				c[i + 1] -= 1;
				c[i] += BASE;
			}
		}
	}
	c = bignum_popzeroes(c);
	return c;
}
Example #2
0
bignum bignum_popzeroes(bignum& c)
{
	if (c.size() > 1)
	{
		while (c.size() > 1 && c.back() == 0)
			c.pop_back();
	}
	return c;
}
Example #3
0
void bignum_print(ostream& print, bignum& c)
{
	c = bignum_popzeroes(c);
	
	cout << c.back();
	if (c.size() - 2 >= 0)
	{
		for (unsigned int i = c.size()-2; i + 1 > 0; i--)
			cout << setfill('0') << setw(3) << c[i];
	}
}