Checkers Forced Jump Rule Check

Detect available mandatory single jumps for declared American/English short kings and forward-capturing men; quiet moves remain merely not barred by captures, not necessarily available. Chained jumps/promotion/other draughts variants omitted.

Description

Short-king checkers uses diagonal captures and a mandatory-capture gate.

Short-king checkers uses diagonal captures and a mandatory-capture gate. Men move toward increasing or decreasing rows according to side sign.^[1]

Enter an 8×8 board using 0,±1 men,±2 kings on dark odd-parity squares and side±1. Enumerate single jumps in row/column order; men use forward directions, kings both. Return jump records, capture-required flag and quiet-move permission when no jump exists.

When to use Checkers Forced Jump Rule Check

Use Checkers Forced Jump Rule Check when you need to evaluate the supplied records under the calculation and evidence rules below. No multiple-jump chains, promotion or proof that any quiet move exists is supplied.

Prepare the supplied game state, observations and explicit variant settings. Follow the card, board, coordinate and state conventions in the calculation rules.

How to use Checkers Forced Jump Rule Check and understand its results

Prepare the supplied game state, observations and explicit variant settings. Follow the card, board, coordinate and state conventions in the calculation rules.
Enter checkerBoard, sideToMove using the field table and calculation rules, then run the tool.
Read availableSingleJumpMoves, forcedCaptureExists, ordinaryQuietMoveAllowed. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
checkerBoard	Checker board	list of list of number	Required
sideToMove	Side to move	number	Required

jump=own piece + adjacent opponent + empty square beyond

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
availableSingleJumpMoves	Available single jump moves	list of list of number
forcedCaptureExists	Forced capture exists	boolean
ordinaryQuietMoveAllowed	Ordinary quiet move allowed	boolean

json

{
  "input": {
    "checkerBoard": [
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        1,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        -1,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ],
      [
        0,
        0,
        0,
        0,
        0,
        0,
        0,
        0
      ]
    ],
    "sideToMove": 1
  },
  "output": {
    "availableSingleJumpMoves": [
      [
        2,
        1,
        4,
        3
      ]
    ],
    "forcedCaptureExists": true,
    "ordinaryQuietMoveAllowed": false
  }
}

Limitations and assumptions

No multiple-jump chains, promotion or proof that any quiet move exists is supplied.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Matrices are limited to 128 rows and 128 entries per row. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use Go Liberty Count Capture Check: A Go group connects stones orthogonally and shares distinct adjacent empty liberties. One liberty indicates atari. For a complementary task, use Stratego Rank Resolve Lookup: Stratego combat includes attack-specific exceptions for the spy and miner. Equal ordinary ranks remove both pieces.

References

Checkers Forced Jump Rule Check — tool.io

Similar or alternative tools

Go Liberty Count Capture Check
A Go group connects stones orthogonally and shares distinct adjacent empty liberties. One liberty indicates atari.
Stratego Rank Resolve Lookup
Stratego combat includes attack-specific exceptions for the spy and miner. Equal ordinary ranks remove both pieces.