#include <iostream>
#include <queue>

using namespace std;
struct Position
{
	int x;
	int y;
};
int n, m;
Position  parents[21][21];
bool used[21][21];
queue<Position> q;

bool Check(int x, int y)
{
	if (x >= 1 && x <= m && y >= 1 && y <= m)
		return true;
	else return false;
}
void proc(Position u, int x, int y, int** dist)
{
	if (Check(x, y) && !used[y][x])
	{
		used[y][x] = true;
		parents[y][x] = u;
		dist[y][x] = dist[u.y][u.x] + 1;
		Position v = { x,y };
		q.push(v);

	}

}
void BFS(Position start, int** dist) {
	used[start.y][start.x] = true;
	parents[start.y][start.x] = start;
	dist[start.y][start.x] = 0;
	Position u{ start.x,start.y };
	q.push(u);
	while (!q.empty()) {
		u = q.front();
		q.pop();

		proc(u, u.x - 1, u.y - 2, dist);
		proc(u, u.x - 1, u.y + 2, dist);
		proc(u, u.x - 2, u.y - 1, dist);
		proc(u, u.x - 2, u.y + 1, dist);
		proc(u, u.x + 1, u.y - 2, dist);
		proc(u, u.x + 1, u.y + 2, dist);
		proc(u, u.x + 2, u.y - 1, dist);
		proc(u, u.x + 2, u.y + 1, dist);



	}
}

void print_way(Position u)
{
	if (parents[u.y][u.x].x != u.x || parents[u.y][u.x].y != u.y)
	{
		print_way(parents[u.y][u.x]);
	}
	cout << u.x << ' ' << u.y << endl;
}
int main()
{
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);


	cin >> n >> m;

	Position start, end;
	int** dist = new int* [21];
	for (int i = 1; i <= 21; i++)
		dist[i] = new int[21];
	cin >> start.x >> start.y;
	cin >> end.x >> end.y;
	BFS(start, dist);


	if (dist[end.y][end.x] > 0)
	{
		cout << dist[end.y][end.x] << endl;
		print_way(end);


	}
	else if (dist[end.y][end.x] == 0)
		cout << 0 << endl << end.x<<" "<<end.y;
	else cout <<-1;



}