On the last days, i needed to fill a codingame test that exposed the following problem that needed to be solved:

In this exercise, you have to analyze records of temperature to find the closest to zero. Sample temperatures. Here, -1.7 is the closest to 0. Implement the function `closestToZero`

to return the temperature closer to zero which belongs to the array `ts`

.

- If
`ts`

is empty, return 0 (zero). - If two numbers are as close to zero, consider the positive number as the closest to zero (eg. if
`ts`

contains -5 and 5, return 5).

- Temperatures are always expressed with floating point numbers ranging from -273 to 5526.
`ts`

is always a valid array and is never`null`

.

## Solution

Based on the exposed data, the following implementation solves the problem:

```
<?php
/**
* From a collection of numbers inside an array, returns the closest value to zero.
*/
function computeClosestToZero(array $ts) {
if(empty($ts)){
return 0;
}
$closest = 0;
for ($i = 0; $i < count($ts) ; $i++) {
if ($closest === 0) {
$closest = $ts[$i];
} else if ($ts[$i] > 0 && $ts[$i] <= abs($closest)) {
$closest = $ts[$i];
} else if ($ts[$i] < 0 && -$ts[$i] < abs($closest)) {
$closest = $ts[$i];
}
}
return $closest;
}
```

You can test the code with different examples of your own:

```
$ts = [7,-10, 13, 8, 4, -7.2,-12,-3.7,3.5,-9.6, 6.5,-1.7, -6.2,7];
// Result: -1.7
echo "Result: " . computeClosestToZero($ts);
$ts = [5, 6, 7, 9 , 2, - 2];
// Result: 2
echo "Result: " . computeClosestToZero($ts);
$ts = [];
// Result: 0
echo "Result: " . computeClosestToZero($ts);
```

Alternatively, one of the solutions of the community includes as well this other option:

```
<?php
function closestToZero(array $ts)
{
if (count($ts) === 0) return 0;
$closest = $ts[0];
foreach ($ts as $d)
{
$absD = abs($d);
$absClosest = abs($closest);
if ($absD < $absClosest)
{
$closest = $d;
}
else if ($absD === $absClosest && $closest < 0)
{
$closest = $d;
}
}
return $closest;
}
```

Happy coding !

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