7.4. On a square board with a side of 2017, a chess bishop stands in the lower left corner. Alexei and Danil take turns moving this bishop, with Alexei moving first, and players are not allowed to move to cells where the bishop has already been (the bishop moves diagonally to any distance). The player who cannot make a move loses. Which of the boys can guarantee a win regardless of the opponent's actions?
Answer: Danil.

Solution: Let's describe Danil's strategy and prove that he is the one who wins.

1) If Alexei's move lands him on the main diagonal, we move to any cell on the same diagonal. This is always possible because initially, there is an even number of unvisited cells on it, and after Alexei's move, there is always an odd number.
2) If Alexei moves to a cell outside the main diagonal, we move to the cell that is symmetric to it relative to the main diagonal. It is clear that this cell could not have been visited before.

Since Danil always has a move available, and the number of cells is finite, Alexei will inevitably lose.

Criteria: only answer - 0 points.

Only strategy without explanation of why it works - no more than 3 points.

If in a similar solution it is not noted why Danil wins due to the finiteness of the game, deduct 1 point.