<?php
$a='Elvis';
$b='Chidera';
$al=strlen($a);
$bl=strlen($b);
$diff=$bl-$al;
$offset=abs($diff);
if($diff>0) {
$twil=$b;
$lite=$a;
}
else {
$twil=$a;
$lite=$b;
}
$tl=strlen($twil); 
$l=strlen($lite);
($tl>$l)?$part1=substr
($twil,0,$offset-1):$part1='';
($tl>$l)?$mix1=substr
($twil,$offset-1,$tl-1):
$mix1=$twil;
$mix1=explode($mix1,'');
$mix2=explode($lite,'');
$mix='';
for($i=0;$i<$l;$i++){
$mix.=$mix1[$i].$mix2[$i];
}
$answer=$part1.$mix;
echo "string1= $a";
echo "string2= $b";
echo $answer;
?>

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