bitwise n-queens solution

bitwisequeens.js

var bitwiseCountNQueensSolutions = function(n) {
  var solutions = 0;
  var allBits = Math.pow(2, n) - 1;

  var bitwiseQueens = function(majorDiag, col, minorDiag) {
    var poss = ~(majorDiag | col | minorDiag) & allBits;
    while (poss) {
      var queenSpot = -poss & poss;
      poss = poss ^ queenSpot;
      bitwiseQueens((majorDiag | queenSpot) >> 1, col | queenSpot, (minorDiag | queenSpot) << 1);
    }
    if (col === allBits) {
      solutions++;
    }
  };

  bitwiseQueens(0,0,0);
  return solutions;
};