Yes, this code is extremely inefficient. If you hand it in for homework, your teach will laugh at you. However, if you're having trouble with the Caesar Cipher, it might help you.

#!/usr/bin/perl

$line = "I'z abg fnlvat lbh nfxrq n ubzrjbex dhrfgvba...";

for ($i = 0; $i < length $line ; $i++) {
   $char = substr $line, $i, 1;
   if ($char eq "a") {
      $char = "n";
   } elsif ($char eq "b") {
      $char = "o";
   } elsif ($char eq "c") {
      $char = "p";
   } elsif ($char eq "d") {
      $char = "q";
   } elsif ($char eq "e") {
      $char = "r";
   } elsif ($char eq "f") {
      $char = "s";
   } elsif ($char eq "g") {
      $char = "t";
   } elsif ($char eq "h") {
      $char = "u";
   } elsif ($char eq "i") {
      $char = "v";
   } elsif ($char eq "j") {
      $char = "w";
   } elsif ($char eq "k") {
      $char = "x";
   } elsif ($char eq "l") {
      $char = "y";
   } elsif ($char eq "m") {
      $char = "z";
   } elsif ($char eq "n") {
      $char = "a";
   } elsif ($char eq "o") {
      $char = "b";
   } elsif ($char eq "p") {
      $char = "c";
   } elsif ($char eq "q") {
      $char = "d";
   } elsif ($char eq "r") {
      $char = "e";
   } elsif ($char eq "s") {
      $char = "f";
   } elsif ($char eq "t") {
      $char = "g";
   } elsif ($char eq "u") {
      $char = "h";
   } elsif ($char eq "v") {
      $char = "i";
   } elsif ($char eq "w") {
      $char = "j";
   } elsif ($char eq "x") {
      $char = "k";
   } elsif ($char eq "y") {
      $char = "l";
   } elsif ($char eq "z") {
      $char = "m";
   }
   $decoded .= $char;
}

print $decoded, "\n";
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