Find the second highest variable in array - php

Question

I would like to find the second highest variable in an array.
For example if I have:
$cookies = array(
"chocolate" => "20",
"vanilla" => "14",
"strawberry" => "18",
"raspberry" => "19",
"bluebery" => "29"
);
I can use max($cookies) to find the highest variable, which is "bluebery" => "29".
But how do I find the second highest? "chocolate" => "20"

Answer 1

Sort it and get the second item is the easiest way:
arsort($cookies);
$keys = array_keys($cookies);
echo $keys[1]; // chocolate
echo $cookies[$keys[1]]; // 20
If you want a more efficient way, you can also do it manually, by keeping track of both the highest and second-highest items at the same time:
function secondMax($arr) {
$max = $second = 0;
$maxKey = $secondKey = null;
foreach($arr as $key => $value) {
if($value > $max) {
$second = $max;
$secondKey = $maxKey;
$max = $value;
$maxKey = $key;
} elseif($value > $second) {
$second = $value;
$secondKey = $key;
}
}
return array($secondKey, $second);
}
Usage:
$second = secondMax($cookies);
echo "{$second[0]} => {$second[1]}"; // chocolate => 20

Answer 2

For fun you could use max() twice :)
For example:
Duplicate the array
Run max()
Remove the max
Run max() again
The alternative would to sort the array based on values and get the second element of the array. I'd be curious which is faster. Likely the sort.

Answer 3

arsort($cookies) AND array_shift($cookies) AND list($k, $v) = each($cookies);
echo "$k => $v"; // chocolate => 20

Answer 4

rsort($cookies);
echo $cookies[1];

Answer 5

Try :
asort($cookies);
end($cookies);
prev($cookies);
list($key,$value) = each($cookies);
or reverse it
arsort($cookies);
reset($cookies);
next($cookies);
list($key,$value) = each($cookies);
** Edit **
I thought I'd share this anyway, if someone would stumble across this and need it :
/**
* Returns the key => value pair with the specific rank.
* if $rank is 0, falase is returned. If $rank is positive,
* then the $rank th smallest pair is returned. If $rank
* is negative, then the $rank th biggest pair is returned.
* If $rank range is outside the size of the array, false
* is returned. If a callable function is provided, it will
* be used to sort the data. If $keySort is true, then the
* data will be sorted by keys instead (the callback functions
* will receive the keys to compare instead of values)
*
* #param $data array
* #param $rank int
* #param $cmd_function callable (optional)
* #param $keySort boolean (optional)
* #return array the key => value pair or false
*/
function findByRank($data, $rank, $cmd_function = null, $keySort = false) {
if (($rank == 0) || (abs($rank) > count($data))) {
return false;
}
$sort = ($keySort?'k':'a').'sort';
if ($cmd_function != null) {
$sort = 'u'.$sort;
$sort($data, $cmd_function);
} else {
$sort($data);
}
if ($rank > 0) {
reset($data);
$next = 'next';
} else {
end($data);
$next = 'prev';
$rank = abs($rank);
}
while (--$rank > 0) $next($data);
return each($data);
}
$cookies = array(
"chocolate" => "20",
"vanilla" => "14",
"strawberry" => "18",
"raspberry" => "19",
"bluebery" => "29"
);
header('Content-type:text/plain; charset=utf-8');
var_dump(findByRank($cookies, -10)); // -> false
var_dump(findByRank($cookies, -2)); // -> 'chocolate' key=>value pair
var_dump(findByRank($cookies, -1)); // -> 'blueberry' key=>value pair
var_dump(findByRank($cookies, 0)); // -> false
var_dump(findByRank($cookies, 1)); // -> 'vanilla' key=>value pair
var_dump(findByRank($cookies, 3)); // -> 'raspberry' key=>value pair

Answer 6

Sort the array descending and take the second value. Or, to be save, take the first value and go through the array until you find a smaller one.

Answer 7

function second_largest($arr)
{
sort($arr, SORT_NUMERIC);
return($arr[count($arr) - 2]);
}
//echo 3
echo second_largest(array(0, 3, 4, 1, 2));

Answer 8

Check this URL
http://maheshbokkisam.blogspot.in/2013/04/find-nth-highest-value-in-array-without.html
Find Nth/ N th highest value from given array without using any sorting in PHP
$ar = array(23,56,87,12,98,85,24,54,99,100,1,4,5,2,76,37,92);
$n = count($ar) - 5;
for($i = 0; $i < $n; $i++){
// Get the max value from array // get the Nth value from last loop
echo $a = max($ar);
echo "<br /><pre>"; print_r($ar);
$ar = array_flip($ar); // Flip the array
//print_r($ar);
unset($ar[$a]); // Unset the max value from array
//print_r($ar);
$ar = array_flip($ar); // Flip the array
echo "</pre>";
echo "<hr />";
}

Answer 9

<?php
// Finding Second highest number (In case of index of array is random)
$arr = [-5 => 33, -4 => -2, 8 => 0, 44, 44, 44, 44, 44];
$max = -INF;
$secondMax = -INF;
$size = sizeof($arr);
if ($size > 1) {
foreach ($arr as $key => $value) {
echo "KEY-> ", $key, "VALUE->", $value, "\n";
if ($value > $max) {
$max = $value;
} else {
if ($value < $max && $value > $secondMax) {
$secondMax = $value;
}
}
}
} else if ($size == 0) {
$max = "No Max element";
$secondMax = "No Second highest element";
} else {
foreach ($arr as $key => $value) {
$max = $arr[$key];
$secondMax = "No second highest element";
}
}
echo "maxvalue = ", $max, "\n";
echo "secondmax =", $secondMax;