**137 人解决**，172 已尝试。

**148 份提交通过**，共有 550 份提交。

**6.7** EMB 奖励。

**单测试点时限: **1.0 秒

**内存限制: **256 MB

There is a chessboard. Queen’s position right now is .

Queen is the most powerful chess. It can be moved any number of unoccupied squares in a straight line vertically, horizontally, or diagonally (in all eight directions).

Bad Queen is a greedy queen. It wants to travel around all the blocks on the chessboard, but don’t want to take too many moves to make that happen. Please devise a route such that Bad Queen can visit all the blocks on the chessboard in exactly moves. The current position is considered as visited.

The input contains four space-separated integers (, , ).

Output the move sequence in order. That is lines. Each line contains a coordinate , separated with space, which is the position after the move.

must be a legal position on chessboard, which means , .

If there are multiple solutions available, you may output any of them.

Input

3 3 1 1

Output

3 3 1 3 2 3 2 1 3 1 2 2 1 2 3 2

Here is the route in the example. 0 is the starting position, and 1 to 8 are the visiting orders.

**137 人解决**，172 已尝试。

**148 份提交通过**，共有 550 份提交。

**6.7** EMB 奖励。

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