PHP implements Fibonacci sequence method

This article mainly introduces the code sharing of Fibonacci sequence in PHP. It has certain reference value. Friends in need can refer to it. I hope it can help everyone.

The Fibonacci sequence refers to a sequence of numbers 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597 , 2584, 4181, 6765, 10946, 17711, 28657, 46368...

This sequence starts from the 3rd item, and each item is equal to the sum of the previous two items.

F0=0, F1=1, Fn=F(n-1)+F(n-2)

Recursive version and non-recursive version.

<?php 
function fib($n){ 
  $array = array(); 
  $array[0] = 1; 
  $array[1] = 1; 
  for($i=2;$i<$n;$i++){ 
    $array[$i] = $array[$i-1]+$array[$i-2]; 
  } 
  print_r($array); 
} 
fib(10); 
echo "\n------------------\n"; 
function fib_recursive($n){ 
  if($n==1||$n==2){return 1;} 
  else{ 
    return fib_recursive($n-1)+fib_recursive($n-2); 
  } 
} 
echo fib_recursive(10); 
?>

As a C and Java programmer, the first time I wrote non-recursive code, I forgot to add $ before the variable. , sad.

Output result

Array 
( 
  [0] => 1 
  [1] => 1 
  [2] => 2 
  [3] => 3 
  [4] => 5 
  [5] => 8 
  [6] => 13 
  [7] => 21 
  [8] => 34 
  [9] => 55 
) 
------------------ 
55

Have you learned how to strike? Hurry up and give it a try.

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Detailed explanation of python output Fibonacci sequence

js implementation of Fibonacci sequence

Recursion and recursion to implement Fibonacci sequence algorithm

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