Can the for loop be eliminated from this piece of PHP code?

Question

I have a range of whole numbers that might or might not have some numbers missing. Is it possible to find the smallest missing number without using a loop structure? If ther

Answer 1

$range = array(0,1,2,3,4,6,7);    
// sort just in case the range is not in order
asort($range);
$range = array_values($range);
$indexes = array_keys($range);
$diff = array_diff($indexes,$range);

echo $diff[0]; // >> will print: 5 
// if $diff is an empty array - you can print 
// the "maximum value of the range plus one": $range[count($range)-1]+1