Fibonacci Words

Fibo words

;
//Project Euler Problem #230 - Fibonacci Words


(function (exports) {
  function getNumber (n) {
    return (127+19*n)*(Math.pow(7,n));
  }

  exports.nFibo = function (n) {
    //Returns the nth part of Fibonacci Sequence
    var s = Math.sqrt(5);
    return Math.round((1/s) * (Math.pow(((1+s)/2),n) - Math.pow(((1-s)/2),n)));
  };

  exports.nWords = function(word, n) {
    //Returns the number of sequence that contains nth number and its length 
    var l = word.length, result;
    n = getNumber(n);
    // console.log(l, n);
    for (var i = 1; i < n; i += 1) {
      result = exports.nFibo(i);
      console.log(i, result);
      if ((result * l) >= n) return {
        nSequence: i,
        sLength: result
      };
    }
  };

  function D (a,b,n) {
    var i = 0, prev = b.length, curr = a.length, sprev = 'B', scurr = 'A', temp = 0, size = 0;

    while (true) {
      temp = curr;
      curr = curr+prev;
      prev = temp;

      temp = scurr;
      scurr = scurr+sprev;
      sprev = temp;
      i += 1;
      if (curr >= n) break;
    }
    var arr = scurr.split('');
    console.log(arr.length);//join().toString().replace(/,/g,''));
    for (var j = 0; j <arr.length; j += 1) {
      var e = arr[j];
      size += (e === 'A' ? a.length : b.length);
      if (size >= n) {
        // console.log("GOT IT:", e, size, n, arr);
        return e === 'A' ? a[size-n-1] : b[size-n-1];
        // return e;
      }
    }
  }


  exports.smash = function (a,b,n) {
    console.log(D(a, b, f(n)));
    // if (n===0) return D(a,b,f(n));

    // return Number(D(a,b,f(n))) + Number(smash(a,b,n-1));
  };  


}(typeof window === 'undefined' ? global : window));

var A = "1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679";

var B = "8214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196";

// console.log(smash(A,B,9));
// smash(A,B, 8);

console.log(nWords(A, 17));