Go Liberty Count Capture Check

Compute orthogonally connected observed Go group and distinct liberties on up to 19×19 board; atari/capture candidates only, no move, suicide, ko/superko or full history legality.

Description

A Go group connects stones orthogonally and shares distinct adjacent empty liberties.

A Go group connects stones orthogonally and shares distinct adjacent empty liberties. One liberty indicates atari.^[1]

Enter a nonempty rectangular board through 19×19 with 0 empty,1 black,2 white, and a valid selected stone coordinate. Return sorted row-major group/liberty coordinates and flags for exactly one or zero liberties.

When to use Go Liberty Count Capture Check

Use Go Liberty Count Capture Check when you need to evaluate the supplied records under the calculation and evidence rules below. No ko, move legality, suicide rule or territory scoring is determined.

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 Go Liberty Count Capture 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 goBoard, selectedRow, selectedColumn using the field table and calculation rules, then run the tool.
Read connectedGroupCells, distinctLibertyCells, libertyCount, inAtari, noLibertiesCaptureCandidate. 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
goBoard	Go board	list of list of number	Required
selectedRow	Selected row	number	Required
selectedColumn	Selected column	number	Required

group=BFS same-color orthogonal neighbors; liberties=distinct adjacent zeros

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

Output field	Meaning	Value type
connectedGroupCells	Connected group cells	list of list of number
distinctLibertyCells	Distinct liberty cells	list of list of number
libertyCount	Liberty count	number
inAtari	In atari	boolean
noLibertiesCaptureCandidate	No liberties capture candidate	boolean

json

{
  "input": {
    "goBoard": [
      [
        0,
        2,
        0
      ],
      [
        2,
        1,
        0
      ],
      [
        0,
        0,
        0
      ]
    ],
    "selectedRow": 1,
    "selectedColumn": 1
  },
  "output": {
    "connectedGroupCells": [
      [
        1,
        1
      ]
    ],
    "distinctLibertyCells": [
      [
        1,
        2
      ],
      [
        2,
        1
      ]
    ],
    "libertyCount": 2,
    "inAtari": false,
    "noLibertiesCaptureCandidate": false
  }
}

Limitations and assumptions

No ko, move legality, suicide rule or territory scoring is determined.

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 Checkers Forced Jump Rule Check: Short-king checkers uses diagonal captures and a mandatory-capture gate. Men move toward increasing or decreasing rows according to side sign. For a complementary task, use Minesweeper Neighbor Mine Count (8-Neighbors): Minesweeper clues count mines in eight neighboring cells. The center cell is never part of its own count.

References

Go Liberty Count Capture Check — tool.io

Similar or alternative tools

Checkers Forced Jump Rule Check
Short-king checkers uses diagonal captures and a mandatory-capture gate. Men move toward increasing or decreasing rows according to side sign.
Minesweeper Neighbor Mine Count (8-Neighbors)
Minesweeper clues count mines in eight neighboring cells. The center cell is never part of its own count.