Check if age groups in multidimensional array conflict - php

Question

array (age) {
[0] ->
[0] =>12
[1] => -
[2] =>16
[1] ->
[0] =>14
[1] => -
[2] =>18
}
I have a dynamic multidimensional array that holds age groups. I want to check these if these age groups overlap one another. In the example above: age group 12-16 would overlap with 14-18 and in this case I want to throw an error.
If tried having nested foreach and for loops but i just can seem to get it right.
heres what I’ve tried:
foreach ($group as $k => $g) {
$g1[] = $g[0];
$g2[] = $g[2];
}
foreach ($g1 as $k => $g) {
if ($g < $g2[$k]) {
foreach ($g2 as $l => $gg) {
if ($gg < $g[$l]) {
echo 'overlap';
}
}
}
}
As you can see I’ve gone with separating the array into two but this doesn’t seem to be effective. Any suggestions?

Answer 1

I would create for both age groups an array range and look if there are any similarities (array_intersect()).
$age_range1 = range($array[0][0], $array[0][2]);
$age_range2 = range($array[1][0], $array[1][2]);
$intersect = array_intersect($age_range1, $age_range2);
if(count($intersect) > 0) {
//throw exception
}
If the age group array is dynamic (more than 2), you need of course to generate the array ranges dynamically and compare it with each other through two loops.
$array = array(0 => array(0 => 12, 2 => 18), 1 => array(0 => 19, 2 => 20), 2 => array(0 => 19, 2 => 35));
$similarities = false;
for($k = 0; $k < count($array); $k++) {
$master = range($array[$k][0], $array[$k][2]);
for($i = 1; $i < count($array); $i++) {
$age_range = range($array[$i][0], $array[$i][2]);
$intersect = array_intersect($master, $age_range);
if(count($intersect) > 0) {
$similarities = true;
break;
}
}
}
if($similarities == true) {
echo 'found exception'; //throw exception
} else {
echo 'found nothing';
}