JavaScript: Display an array of Fibonacci numbers on the screen

Set n , which must be greater than or equal to 0, then:

 var f = [0, 1]; //Первые значения if (n <= 2) { //если n <= 2 var result = f.slice(0, n); //записываем в результат срез f от 0 до n } else { for (i = 0; i < n - 2; i++) { // повторяем n-2 раза, т.к. 2 элемента уже есть f.push(f[f.length - 1] + f[f.length - 2]); //заполняем (n+2)-й элемент } var result = f; //записываем в result наш массив f } alert(result); //вывод result на экран (через алерт) 

f[f.length - 1] gets the last element of the array, f[f.length - 2] - the penultimate.

Array.Push () - the method of inserting the element at the end of the array.

Array.Slice () - method returning array slice

Here infa generally about arrays.

Wrap all the code in the f-yu:

 function fibi(n) { // число n передадим параметром в ф-ю 

Initialize the variable that will contain the current value of the sum:

  var sum = 0 

iteration counter:

  ,i 

text string for array output:

  ,str 

and the array itself:

  ,arr = [] ; 

Twist the loop, where we will count the iterations to reach n:

  for( i=0; i<n; i++) { 

The next value of the array is obtained by adding to the “current” sum (later we insert it at the end of the array) of the last but one element of the array. There are two special cases: when the array is empty, we insert 0; and when there is only one element in it, then we add one to the tail.

  if( arr.length > 1) sum += arr[ arr.length-2]; if( arr.length == 1) sum = 1; if( arr.length == 0) sum = 0; 

We push this value into the end of the array:

  arr.push( sum); 

End of the cycle - repeat, but do not shake:

  } 

Get the array as a string for output:

  str = arr.join(", "); // склеить элементы массива запятой-с-пробелом 

Print to console:

  console.log(str); 

Or in the document, since there is a "web programming" tag:

  document.body.innerHTML = str; 

End of code and f-s:

 } 

Checking :

 fibi(4); // выводит 0, 1, 1, 2 

If it is completely lazy, then you can solve it like this:

 var fibonacci = new Array(0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946); alert(fibonacci); 

but in general google "javascript arrays" - everything is elementary there.