Groebner_HFE80/polynomial.cpp

#include "polynomial.h"
Polynomial::Polynomial()
{
	mono.clear();
	leader_order = -1;
	degree = -1;
}
bool Polynomial::input(istream& in)
{
	int state = 0;    //0：记录，1：记录变量编号，2：忽略，3：零单项式
	char vari[D] = { 0 };
	int vari_place = 0;
	int now_vari = 0;
	Monomial m;
	bool first = true;
	while (1)
	{
		char c;
		in.get(c);
		if (c == 'x')
		{
			state = 1;
			first = false;
		}
		else if (c >= '0' && c <= '9')
		{
			if (state == 0)   //单独的数字：奇数不做处理，偶数将该单项式置为零单项式
			{
				if (c % 2 == 0)
					state = 3;
				else
					state = 4;
			}
			if (state == 1)
			{
				now_vari *= 10;
				now_vari += c - '0';
			}
			first = false;
		}
		else if (c == '*')
		{
			state = 0;
			vari[vari_place++] = now_vari;
			now_vari = 0;
		}
		else if (c == '+')
		{
			if (state == 4)
			{
				m.from_factor(vari, vari_place);
				mono.add(m.order);
			}
			else if (state != 3)
			{
				vari[vari_place++] = now_vari;
				m.from_factor(vari, vari_place);
				mono.add(m.order);
			}
			state = 0;
			now_vari = 0;
			vari_place = 0;
		}
		else if (c == '^')
		{
			state = 2;
		}
		else if (c == ' ');    //不进行任何操作
		else if (c == '\n' || c == '\r')
		{
			if (!first)
			{
				if (state == 4)
				{
					m.from_factor(vari, vari_place);
					mono.add(m.order);
				}
				else if (state != 3)
				{
					vari[vari_place++] = now_vari;
					m.from_factor(vari, vari_place);
					mono.add(m.order);
				}
				state = 0;
				now_vari = 0;
				vari_place = 0;
			}
			else
			{
				state = 0;
				now_vari = 0;
				vari_place = 0;
			}
			break;
		}
		else
			break;

	}
	set_leader_degree();
	return !first;
}

void Polynomial::input_order(istream& in)
{
	int max = -1;
	while (!in.eof())
	{
		int temp = 0;
		in >> temp;
		if (temp != -1)
		{
			mono.set(temp);
			if (max < temp)
				max = temp;
		}
		else
			break;
	}
	leader_order = max;
}

void Polynomial::print(ostream& out)
{
	Monomial m;
	bool first = true;
	for (int i = M - 1; i >= 0; i--)
	{
		if (mono.get(i))
		{
			m.from_order(i);
			if (!first)
				out << '+';
			else
				first = false;
			m.print(out);
		}
	}
	out << endl;
}

void Polynomial::print_order(ostream& out)
{
	for (int i = M - 1; i >= 0; i--)
	{
		if (mono.get(i))
			out << setw(4) << i;
	}
	out << endl;
}

bool Polynomial::get(int n)
{
	return mono.get(n);
}

void Polynomial::add(int n)   //添加项序第n小的单项式，如果该单项式已存在则抵消
{
	mono.add(n);   //将位图对应位置取反
}
void polynomial_mul(Polynomial& ret, Polynomial& p, Monomial& m)
{
	Monomial mtemp;
	for (int i = 0; i < M; i++)
	{
		if (p.get(i))
		{
			ret.add(mult_res[m.order][i]);
		}
	}
}
void Polynomial::set_leader_degree(int max_leader)
{
	leader_order = mono.getleader();
	if (leader_order != -1)
	{
		for (int i = 0; i <= D; i++)
		{
			degree = i;
			if (leader_order < grevlex_degree_interval[i])
				break;
		}
	}
	else
	{
		degree = -1;
	}
}
Polynomial& Polynomial::operator ^=(Polynomial& p)
{
	this->mono.xor_part(p.mono, 0, (max(leader_order, p.leader_order) - 1) / 64 + 2);
	set_leader_degree(max(this->leader_order, p.leader_order));
	return *this;
}
Polynomial& Polynomial::operator ^=(Sparse_Polynomial& p)
{
	for (int i = 0; i < p.length; i++)
	{
		mono.add(p.sparse_mono[i]);
	}
	set_leader_degree(max(this->leader_order, p.leader_order));
	return *this;
}
bool Polynomial::iszero()
{
	if (mono.data_len <= 0 || leader_order < 0)
		return true;
	return false;
}
Monomial Polynomial::get_leader()
{
	Monomial ret;
	ret.from_order(leader_order);
	return ret;
}
bool operator > (Polynomial& p, Polynomial& q)
{
	return p.mono > q.mono;
}

bool operator < (Polynomial& p, Polynomial& q)
{
	return p.mono < q.mono;
}