Find highest value in multi dimensional array

Question

Here is the multi dimensional array

$arr = array(
 array(141,151,161), 
 2, 
 3, 
 array(
 101, 
 202, 
 array(303,404)
 )
);

How to find the highest value, which the result in the array above should be 404.
The array depth can may be more than 3.

---

Here is the code i last tried, but i notice this only can check until 3 depth, i need it can be check unlimited depth

function MaxArray($arr){
 foreach($arr as $valueDepth1){
 if(is_array($valueDepth1)){
 foreach($valueDepth1 as $valueDepth2){
 if(is_array($valueDepth2)){
 foreach($valueDepth2 as $valueDepth3){
 $checingArray[]=$valueDepth3;
 }
 }else{
 $checingArray[]=$valueDepth2;
 } 
 }
 }else{
 $checingArray[]=$valueDepth1;
 }
 }
 return max($checingArray);
}

• Smamatti: This is not a give me the code site. Write a recursive function which calls itself, when the type of the child is an array. take a look at is_array(): php.net/manual/en/function.is-array.php
• GusDeCooL: @Smamatti: yes i understand this is not a give code site. I tried to create the code. But cannot find the best logic to make the function.
• GusDeCooL: @Smamatti: Thank you for the link, i already tried with that method before. The logic i didn't understand yet is Write a recursive function which calls itself like as you said.
• GusDeCooL: @Marcus: i edited my question, thats is my last code. I purposely didn't write the code here in the first because i know it dull code and bad logic.

Answer 1

function highest($array) {
 foreach($array as $key => $value) {
 if (is_array($value)) {
 $array[$key] = highest($value);
 }
 }
 sort($array);
 return array_pop($array);
}

You can see it in action here: http://codepad.org/4xPFsU1U

• GusDeCooL: thank you, the best logic i've seen. I didn't now if we can dow self method inside the function.
• dimme: Calling the method itself within the method is called Recursion. It it very useful in many cases. Although you should be careful with it as for every recursive call you increase the stack size.

Answer 2

You could try something like this:

$max = -1;
array_walk_recursive($arr, 'arrmax');
function arrmax($item, $key) {
 global $max;
 $max = ($key > $max) ? $key : $max;
}
echo "Maximum number is : " . $max;

• Aurelio De Rosa: What if the value are all < -1 ?
• Steve Lewis: I'd say: set $max to null at beginning, change conditional to (is_null($max) || $key > $max)
• Pradeep: @Steve Or you can set $max to -INF

Answer 3

Here's a function I found on the first page on google. Search engines is a perfect place to find stuff ;)

function recursive_array_max($a) {
 foreach ($a as $value) {
 if (is_array($value)) {
 $value = recursive_array_max($value);
 }
 if (!(isset($max))) {
 $max = $value;
 } else {
 $max = $value > $max ? $value : $max;
 }
 }
 return $max;
}

Source

Answer 4

This can be a good starting point:

getMax($array)
{
 if ( is_array($array) )
 {
 // NOTE: PHP_MIN doesn't exist. Is just to let you understand the logic
 $max = PHP_MIN; 
 foreach($array as $value)
 {
 if ( is_array($value) )
 $value = getMax($value);
 if ($value > $max)
 $max = $value;
 }
 return $max;
 }
 else
 return $array
}

Answer 5

Try This

function MaxRecursive($arr,$maxVal = null)
{
 try {
 if(! isset($arr) || ! is_array($arr) )
 throw new Exception("The array is empty");
 for($i=0;$i<count($arr);$i++)
 {
 if(is_array($arr[$i]))
 $maxVal = MaxRecursive($arr[$i],$maxVal);
 else
 {
 if($maxVal == null)
 $maxVal = $arr[$i];
 if($arr[$i] > $maxVal )
 $maxVal = $arr[$i];
 }
 }
 return $maxVal;
 }
 catch (Exception $e)
 {
 echo $e->getMessage();
 }
}
function MaxArray2($arr)
{
 return MaxRecursive($arr,null);
}

Answer 6

getMax($arr); 
function getMax($arr) { 
 foreach($arr as $arrr) { 
 echo max($arrr[2]); 
 }
}

Answer 7

You have to use recursion, with a single loop. For each element, if it is a number, we compare it with the current highest value, if it is an array we call the function recursively to check the array:

 function getHeighestNumber($array = array()) {
 static $number = 0;
 foreach ($array AS $key=>$value) {
 if(is_array($value)) { 
 $number = getHeighestNumber($value);
 } else if($value > $number) {
 $number = $value;
 } 
 }
 return $number;
 }