first commit

packages/draughts/computer/quiescence-search.js

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+import { evaluateBoard } from './evaluate-board';
+
+export function quiescenceSearch(board, alpha, beta) {
+  const baseE = evaluateBoard(board);
+
+  if (baseE >= beta) return beta;
+  alpha = Math.max(baseE, alpha);
+
+  for (const move of board.moves) {
+    if (move.captures.length <= 0) continue;
+
+    const nextBoard = board.doMove(move);
+    const e = -quiescenceSearch(nextBoard, -beta, -alpha);
+
+    if (e >= beta) return beta;
+    alpha = Math.max(e, alpha);
+  }
+
+  return alpha;
+}