<?php

function solution($S, $K) {
    $S = trim($S);
    $parts = array();
    while (strlen($S) > $K) {
        $part = substr($S, 0, $K);
        $lastSpace = strrpos($part, ' ');

        $parts[] = substr($S, 0, $lastSpace);
        $S = substr($S, $lastSpace);
    }
    $parts[] = $S;

    var_dump($parts);

    if (count($parts) == 1) return -1;
    return count($parts);
}

$ch = curl_init();
curl_setopt_array($ch, array(
    CURLOPT_URL => 'http://hiepnt.s3.amazonaws.com/media/catalog/product/n/o/nov13-anh-test22.jpg',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_NOBODY => true,
    CURLOPT_HEADER => true
));
curl_exec($ch);
$info = curl_getinfo($ch, CURLINFO_HTTP_CODE);

var_dump($info);
var_dump(solution("SMS messages are really short",12));