Minimum Queen Moves to Reach Target

Problem Statement

There is an 8 x 8 empty chessboard with 1-indexed rows and columns.

You are given source = [sr, sc], the starting position of a queen, and target = [tr, tc], the target position.

In one move, the queen travels one or more squares along a single row, column, or diagonal, staying within the board.

Return the minimum number of moves for the queen to land exactly on target.

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Input / Output

Input: source = [8,1], target = [1,8] Output: 1 Explanation: One diagonal move. Input: source = [4,2], target = [1,3] Output: 2 Explanation: (4,2) → (4,3) → (1,3) Input: source = [1,1], target = [1,1] Output: 0

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Constraints

source == [sr, sc] target == [tr, tc] 1 ≤ sr, sc, tr, tc ≤ 8

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Understanding the Problem

The answer can only be 0, 1 or 2:

• 0 → already on target
• 1 → same row, same column, or same diagonal (|sr - tr| == |sc - tc|)
• 2 → otherwise: move along the row to column , then along the column to row (a queen moves like a rook, and a rook reaches any square in ≤ 2 moves)