PHP implementation of the Joseph ring problem using PHP array internal pointer operation functions_PHP tutorial

Let’s take a look at the detailed description of this problem:
view sourceprint? A group of monkeys line up in a circle, numbered sequentially by 1,2,...,n. Then start counting from the 1st one, count to the mth one, kick it out of the circle, start counting from behind it, count to the mth one, kick it out..., and continue in this way. Until there is only one monkey left, that monkey is called the king. Programming is required to simulate this process, input m, n, and output the number of the last king.
When I first conceived the idea, I wanted to use PHP arrays to implement it (of course, I still used arrays in the end), and then simulated the internal pointer of an array. It turned out that it was not that easy to simulate an "array pointer" because it involved a lot of " Pointer" operation, finally suddenly thought, PHP array itself has internal pointers, why should we "reinvent the wheel"? ! So~ look at the code:

Copy code The code is as follows:

function getKingMonkey($n, $m)
{
$a = array();//Declare internal array
for($i = 1; $i <= $n; $i ++)
{
$a[$ i] = $i;//This step is correct
}
reset($a);//For the sake of rigor, let’s use a reset() function. In fact, we can also omit the
while(count( $a) > 1)//The main loop begins. The criterion used here is to stop the loop when the number of array elements is equal to 1
{
for($counter = 1; $counter <= $ m; $counter++)//Nested for loop, used to "kick out" the monkeys that count to m
{
if(next($a)){//If there is a next element
if ($counter == $m)
{
unset($a[array_search(prev($a), $a)]);//When counting to m, use unset() to delete array elements
}
}
else//If there is no next element
{
reset($a);//The first element of the array acts as the next element
if($counter == $m)
{
unset($a[array_search(end($a), $a)]);//When the count reaches m, use unset() to delete the array elements. Note here end()
reset($a);//Remember to "return" the internal pointer of the array
}
}
}
}
return current($a);
}

Test it:
echo "The number of the Monkey King is:" . getKingMonkey(100, 17);
The output is:
view sourceprint?Monkey King The number is: 53
The Ｅｎｄ

http://www.bkjia.com/PHPjc/322540.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/322540.htmlTechArticleLet’s take a look at the detailed description of this problem: view sourceprint? A group of monkeys line up in a circle, press 1,2, ...,n are numbered in sequence. Then start counting from the 1st one, count to the mth one, kick it out of the circle, start from it...