Comment by shwestrick

Enjoyed playing with this!

N-queens search is another nice recursive example. E.g. call this with nqueens(0, 5, [])

    function nqueens(i:number, n:number, queens: number[][]) {
      if (i >= n) return 1;

      let count = 0;
      for (let j = 0; j < n; j++) {

        let is_threatened = false;
        for (let k = 0; k < queens.length; k++) {
          let x = queens[k][0];
          let y = queens[k][1];

          if (i == x || j == y || i - j == x - y || i + j == x + y) {
            is_threatened = true;
            break;
          }
        }

        if (is_threatened) continue;

        count += nqueens(i+1, n, Array(Array(i,j)).concat(queens))
      }

      return count;
    }