<?php
 
function unique2($palavra){
    $ret = "";
 
    for ($i = 0; $i < strlen($palavra); $i++){
    	if ($i == 0 || $palavra[$i] != $palavra[$i - 1]) $ret .= $palavra[$i];
    }
    return $ret;
}
 
echo unique2("Banana") . "\n";        // Banana
echo unique2("Arara") . "\n";         // Arara
echo unique2("assassinos") . "\n";    // asasinos
echo unique2("Marreco") . "\n";       // Mareco
echo unique2("Elllizabettth") . "\n"; // Elizabeth
echo unique2("FooBaaar") . "\n";      // FoBar
echo unique2("Woow") . "\n";          // Wow
echo unique2("baazz") . "\n";         // baz

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