(PHP) Checking items in an array

See the documentation for array_count_values(). It seems to be what you are looking for.

$array = array('a', 'b', 'c', 'a', 'b');
$counts = array_count_values($array);
printf("Number of 'b's: %d\n", $counts['b']);
var_dump($counts);

Output:

Number of 'b's: 2

array(3) {
["a"]=> int(2)
["b"]=> int(2)
["c"]=> int(1) }

Use array_count_values($arr). This returns an associative array with each value in $arr as a key and that value's frequency in $arr as the value. Example:

$arr = array(1, 2, 3, 4, 2);
$counts = array_count_values($arr);
$count_of_2 = $counts[2];

You can count the number of instances by using this function..

 $b = array(a,b,c,a,b);

 function count_repeat($subj, $array) {
    for($i=0;$i<count($array);$i++) {
       if($array[$i] == $subj) {
           $same[] = $array[$i]; //what this line does is put the same characters in the $same[] array.
        }
    return count($same);
 }

echo count_repeat('b', $b); // will return the value 2

Although there are some fancy ways, a programmer should be able to solve this problem using very basic programming operators.
It is absolutely necessary to know how to use loops and conditions.

$count = 0;
$letters= array("a","b","c","a","b"); 
foreach ($letters as $char){
  if ($char == "b") $count = $count+1;
}
echo $count.' "b" found';

NOT a rocket science.