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+## DNS Calculator
+
+Do simple mathematical operations using DNS queries.
+
+    $ dig @ns.dus.kyouma.net +short txt 1-a-4-m-50-d-250.calc.emily.cat
+    "1.8"
+    $ dig +short txt calc.help.emily.cat
+    "operators are a (add), s (subtract), m (multiply), and d (divide)."
+    "separate tokens with '-' or '.'"
+
+It should work on every DNS server but sometimes it’s buggy. If you don’t get a result try to specify ns.dus.kyouma.net as nameserver.