Kode apa ini

<form method="POST" action="index.php">
    KUNCI 1 <input type="text" name="kunci1"><br />
    KUNCI 2 <input type="text" name="kunci2"><br />
    KUNCI 3 <input type="text" name="kunci3"><br />
    KUNCI 4 <input type="text" name="kunci4"><br />
    KUNCI 5 <input type="text" name="kunci5"><br />
    KUNCI 6 <input type="text" name="kunci6"><br />
    <input type="submit" value="enkripsi">
</form>
<?php
//data input kunci
@$kunci1 = $_POST["kunci1"];
@$kunci2 = $_POST["kunci2"];
@$kunci3 = $_POST["kunci3"];
@$kunci4 = $_POST["kunci4"];
@$kunci5 = $_POST["kunci5"];
@$kunci6 = $_POST["kunci6"];

//data kunci
$array_abjad1 = array("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z");
//..........
$array_key1 = array("A","R","I","F","H","M","N","B","C","D","E","G","J","K","L","O","P","Q","S","T","U","V","W","X","Y","Z");
$array_key2 = array("N","I","A","L","R","S","T","B","C","D","E","F","G","H","J","K","M","O","P","Q","U","V","W","X","Y","Z");
$array_key3 = array("C","H","R","I","S","T","N","E","A","B","D","F","G","J","K","L","M","O","P","Q","U","V","W","Z","Y","Z");
$array_key4 = array("S","E","H","A","T","M","L","B","C","D","F","G","I","J","K","N","O","P","Q","R","U","V","W","X","Y","Z");
$array_key5 = array("H","I","D","U","P","N","A","B","C","E","F","G","J","K","L","M","O","Q","R","S","T","V","W","X","Y","Z");
$array_key6 = array("Y","O","G","A","K","R","T","B","C","D","E","F","H","I","J","L","M","N","P","Q","S","U","V","W","X","Z");

//KUNCI1..................................
//kunci1
@$key1_hasil_kunci1 .= "";
for($i=0;$i<=25;$i++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$i]"=>"$array_key1[$i]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci1 == $row_data_kunci1){
            $key1_hasil_kunci1=$row_detail_data_kunci1;
        }
    }
}
//kunci3
@$key1_hasil_kunci3 .= "";
for($a=0;$a<=25;$a++){
    $data1_kunci1 = array("$array_key3[$a]"=>"$array_abjad1[$a]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key1_hasil_kunci1 == $row_data_kunci1){
            $key1_hasil_kunci3 = $row_detail_data_kunci1;
        }
    }
}
//kunci5
@$key1_hasil_kunci5 .= "";
for($b=0;$b<=25;$b++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$b]"=>"$array_key5[$b]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key1_hasil_kunci3 == $row_data_kunci1){
            $key1_hasil_kunci5 = $row_detail_data_kunci1;
        }
    }
}
echo $key1_hasil_kunci5;

//KUNCI3...........................................
//kunci3
@$key3_hasil_kunci3 .= "";
for($c=0;$c<=25;$c++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$c]"=>"$array_key3[$c]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci3 == $row_data_kunci1){
            $key3_hasil_kunci3=$row_detail_data_kunci1;
        }
    }
}
//kunci5
@$key3_hasil_kunci5 .= "";
for($d=0;$d<=25;$d++){
    $data1_kunci1 = array("$array_key5[$d]"=>"$array_abjad1[$d]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key3_hasil_kunci3 == $row_data_kunci1){
            $key3_hasil_kunci5 = $row_detail_data_kunci1;
        }
    }
}
//kunci1
@$key3_hasil_kunci1 .= "";
for($e=0;$e<=25;$e++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$e]"=>"$array_key1[$e]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key3_hasil_kunci5 == $row_data_kunci1){
            $key3_hasil_kunci1 =  $row_detail_data_kunci1;
        }
    }
}
echo $key3_hasil_kunci1;

//KUNCI5.............................................
//kunci5
@$key5_hasil_kunci5 .= "";
for($f=0;$f<=25;$f++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$f]"=>"$array_key5[$f]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci5 == $row_data_kunci1){
            $key5_hasil_kunci5=$row_detail_data_kunci1;
        }
    }
}
//kunci1
@$key5_hasil_kunci1 .= "";
for($g=0;$g<=25;$g++){
    $data1_kunci1 = array("$array_key1[$g]"=>"$array_abjad1[$g]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key5_hasil_kunci5 == $row_data_kunci1){
            $key5_hasil_kunci1 = $row_detail_data_kunci1;
        }
    }
}
//kunci3
@$key5_hasil_kunci3 .= "";
for($h=0;$h<=25;$h++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$h]"=>"$array_key3[$h]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key5_hasil_kunci1 == $row_data_kunci1){
            $key5_hasil_kunci3 =  $row_detail_data_kunci1;
        }
    }
}
echo $key5_hasil_kunci3;

//KUNCI2..............................................
//kunci2
@$key2_hasil_kunci2 .= "";
for($j=0;$j<=25;$j++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$j]"=>"$array_key2[$j]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci2 == $row_data_kunci1){
            $key2_hasil_kunci2=$row_detail_data_kunci1;
        }
    }
}
//kunci4
@$key2_hasil_kunci4 .= "";
for($k=0;$k<=25;$k++){
    $data1_kunci1 = array("$array_key4[$k]"=>"$array_abjad1[$k]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key2_hasil_kunci2 == $row_data_kunci1){
            $key2_hasil_kunci4 = $row_detail_data_kunci1;
        }
    }
}
//kunci6
@$key2_hasil_kunci6 .= "";
for($l=0;$l<=25;$l++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$l]"=>"$array_key6[$l]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key2_hasil_kunci4 == $row_data_kunci1){
            $key2_hasil_kunci6 = $row_detail_data_kunci1;
        }
    }
}
echo $key2_hasil_kunci6;

//KUNCI4..............................................
//kunci4
@$key4_hasil_kunci4 .= "";
for($m=0;$m<=25;$m++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$m]"=>"$array_key4[$m]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci4 == $row_data_kunci1){
            $key4_hasil_kunci4=$row_detail_data_kunci1;
        }
    }
}
//kunci6
@$key4_hasil_kunci6 .= "";
for($n=0;$n<=25;$n++){
    $data1_kunci1 = array("$array_key6[$n]"=>"$array_abjad1[$n]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key4_hasil_kunci4 == $row_data_kunci1){
            $key4_hasil_kunci6 = $row_detail_data_kunci1;
        }
    }
}
//kunci2
@$key4_hasil_kunci2 .= "";
for($o=0;$o<=25;$o++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$o]"=>"$array_key2[$o]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key4_hasil_kunci6 == $row_data_kunci1){
            $key4_hasil_kunci2 = $row_detail_data_kunci1;
        }
    }
}
echo $key4_hasil_kunci2;

//KUNCI6..............................................
//kunci6
@$key6_hasil_kunci6 .= "";
for($p=0;$p<=25;$p++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$p]"=>"$array_key6[$p]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($kunci6 == $row_data_kunci1){
            $key6_hasil_kunci6=$row_detail_data_kunci1;
        }
    }
}
//kunci6
@$key6_hasil_kunci2 .= "";
for($q=0;$q<=25;$q++){
    $data1_kunci1 = array("$array_key2[$q]"=>"$array_abjad1[$q]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key6_hasil_kunci6 == $row_data_kunci1){
            $key6_hasil_kunci2 = $row_detail_data_kunci1;
        }
    }
}
//kunci2
@$key4_hasil_kunci4 .= "";
for($r=0;$r<=25;$r++){
    //key1
    $data1_kunci1 = array("$array_abjad1[$r]"=>"$array_key4[$r]");
    foreach ($data1_kunci1 as $row_data_kunci1 => $row_detail_data_kunci1){
        if($key6_hasil_kunci2 == $row_data_kunci1){
            echo $key4_hasil_kunci4 = $row_detail_data_kunci1;
        }
    }
}
$key4_hasil_kunci4;
?>