Please let me know where I am doing the mistake. 
print "Please enter a string:\n";
$string=<>;
chomp ($string);
# The first position in the string.
$position = 0;

while ($position < length($string))
{
    $char = lc(substr($string, $position, 1));

    if ($char ne "a")
    {
        last;
    }

    # Increment the position
    $position++;
    
}
 
if ($postion == length($string))
{
    print "The string you entered is all A's!\n";
}
else
{
    print "At least one of the characters in the string " .
        "you entered is not \"A\".\n";
}

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output I am getting everytime is "At least one of the characters in the string you entered is not "A"

In reply to my script is not giving the result using last function by ulaksh

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