PHP implementation of offer jumping steps example

This article mainly shares with you an example of how to implement offer jumping in PHP. I hope it can help you. Let's look at an example first. A frog can jump up one step at a time, or it can jump up two steps... It can also jump up n steps. Find out how many ways the frog can jump up an n-level staircase.

Idea: Based on the Fibonacci sequence:

F(N)=F(N-1)+F(N-2)+F(N-3)+F (N-4)+.....F(2)+F(1)

F(N-1)=F(N-2)+F(N-3)+F(N -4)+.....+F(2)+F(1)

Subtract the two to get: F(N-1)=2*F(N-1)

<?php

function jumpFloorII($number)
{
	$arr[0]=0;
	$arr[1]=1;
	$arr[2]=2;
 
		for($i=3;$i<=$number;$i++)
	{
		$arr[$i]=2*$arr[$i-1];
	}
	 
	
	return $arr[$number];
}

Related recommendations:

There are n levels in a step. If you can jump 1 level or 2 levels at a time, find the total number

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