Fibonacci JS

by Thinkscape

CSS

body { font-family: Arial, sans-serif; }

JavaScript

var a = [0, 1, 1];
for (var x = 4; x<=10; x++) {
  a.shift();
	a.push(a[0] + a[1])
  document.write('list push+shift |  ' + x + ": " + a[2] + '<br>');
}

var b = [0, 1];
for (var x = 2; x<=10; x++) {
  b[x] = b[x-2] + b[x-1]; 
  document.write('list set |   ' + (x+1) + ": " + b[x] + '<br>');
}

var a = 0, b = 1, c = 1;
for (var x = 3; x<=10; x++) {
  a = b;
  b = c
  c = a+b;
  document.write('var |   ' + x + ": " + c + '<br>');
}

var a = 0, b = 1;
for (var x = 3; x<=10; x++) {
  [a, b] = [b, a + b];
  document.write('swap with spread |   ' + x + ": " + b + '<br>');
}



// document.write(cur);

//fib(n) = fib(n-2) + fib(n-1);
 
// 0, 1
// 0, 1, 1
// 0, 1, 1, 2
// 0, 1, 1, 2, 3