CP-codes/Gaussian Elimination.cpp at master · Vivekvar/CP-codes · GitHub

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struct Gauss
{
	int bits = 60;
	vector<int> table;

	Gauss()
	{
		table = vector<int> (bits, 0);
	}

	Gauss(int _bits)
	{
		bits = _bits;
		table = vector<int> (bits, 0);
	}

	int size()
	{
		int ans = 0;
		for(int i = 0; i < bits; i++)
		{
			if(table[i])
				ans++;
		}
		return ans;
	}

	bool can(int x)
	{
		for(int i = bits - 1; i >= 0; i--)
			x = min(x, x ^ table[i]);
		return x == 0;
	}

	void add(int x)
	{
		for(int i = bits - 1; i >= 0 && x; i--)
		{
			if(table[i] == 0)
			{
				table[i] = x;
				x = 0;
			}
			else
				x = min(x, x ^ table[i]);
		}
	}

	int getBest()
	{
		int x = 0;
		for(int i = bits - 1; i >= 0; i--)
			x = max(x, x ^ table[i]);
		return x;
	}

	void merge(Gauss &other)
	{
		for(int i = bits - 1; i >= 0; i--)
			add(other.table[i]);
	}
};