How to add the values of multidimensional arrays in PHP? - php

Question

Problem solved thanks guys :
foreach($FIMP as &$value){
foreach($value as &$values){
$values[0]=$values[3].$values[2].$values[1];
}
I have the following arrays:
$FIMP=array(
1 => array(
1 => array('a','b','c')
2 => array('a1','b1','c1')
2 => array(
1 => array('a2','b2','c2')
3 => array(
1 => array('a3','b3','c3')
2 => array('a4','b4','c4')
3 => array('a5','b5','c5')
)
I want to add the the values: b and c and overwrite a with the 'bc'
result like this
$FIMP=array(
1 => array(
1 => array('bc','b','c')
2 => array('b1c1','b1','c1')
2 => array(
1 => array('b2c2','b2','c2')
...
I already tried $FIMP
foreach($FIMP as $value){
foreach($value as $values){
$values[0]=$values[3].$values[2].$values[1];
}
}
in the out put there is no change to the previous $FIMP ,

Answer 1

From the PHP foreach documentation:
In order to be able to directly modify array elements within the loop precede $value with &. In that case the value will be assigned by reference.
So to change the values in $FIMP, you need to change your foreach loop to the following:
foreach($FIMP as &$value){
foreach($value as &$values){
// alter $value or $values here
}
}

Answer 2

<?php
$FIMP=array(
1 => array(
1 => array('a','b','c'),
2 => array('a1','b1','c1'),
),
2 => array(
1 => array('a2','b2','c2'),
),
3 => array(
1 => array('a3','b3','c3'),
2 => array('a4','b4','c4'),
3 => array('a5','b5','c5'),
),
);
foreach($FIMP as & $v1){
foreach($v1 as & $v2){
$v2[0] = $v2[1].$v2[2];
}
}
var_dump($FIMP);

Answer 3

You can do it like this:
foreach($FIMP as &$first){
foreach($first as &$second){
$second[0] = $second[1].$second[2];
}
}
OUTPUT
Array
(
[1] => Array
(
[1] => Array
(
[0] => bc
[1] => b
[2] => c
)
[2] => Array
(
[0] => b1c1
[1] => b1
[2] => c1
)
)
[2] => Array
(
[1] => Array
(
[0] => b2c2
[1] => b2
[2] => c2
)
)
[3] => Array
(
[1] => Array
(
[0] => b3c3
[1] => b3
[2] => c3
)
[2] => Array
(
[0] => b4c4
[1] => b4
[2] => c4
)
[3] => Array
(
[0] => b5c5
[1] => b5
[2] => c5
)
)
)