This might just be the fastest possible non-bitwise JavaScript algorithm for the N Queens puzzle http://en.wikipedia.org/wiki/Eight_queens_puzzle. This was written in collaboration with githib.com/stites

nqueens.js

var nQueens = function(n){
  if(n === 1){ return 1; }

  n = n - 1;

  var
    m     = Math.ceil(n/2),
    count = 0,
    col   = new Int8Array(n + 1),
    maj   = new Int8Array(n + n + 1),
    min   = new Int8Array(n + n + 1);

  var recurse = function(x, col, maj, min){
    for(var y = 0; y <= n; y++){
      if(maj[n + x - y] || min[x + y]){
        continue;
      }
      if(!col[y]){
        if(x === n){
          return count++;
        }
        col[y] = 1; 
        maj[n + x - y] = 1; 
        min[x + y] = 1;
        recurse(x + 1, col, maj, min);
        col[y] = 0; 
        maj[n + x - y] = 0; 
        min[x + y] = 0;
      }
    }
  }
 
  for(var i = 0; i < m; i++){
    col[i] = 1;
    maj[n - i] = 1;
    min[i] = 1;
    recurse(1, col, maj, min);
    col[i] = 0;
    maj[n - i] = 0;
    min[i] = 0;
  }

  count *= 2;

  if(!(n % 2)){
    col[m] = 1;
    maj[n - m] = 1;
    min[m] = 1;
    recurse(1, col, maj, min);
  }

  return count;
}