initial commit

bash/secret-handshake/secret_handshake.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+
+num=$1
+
+strings=(
+    "wink"
+    "double blink"
+    "close your eyes"
+    "jump"
+)
+reverse=n
+result=()
+
+(( $num & 2#10000 )) && reverse=y
+
+# get matching bits
+for (( i=0 ; i<4 ; ++i )); do
+    (( $num & 1<<$i )) && result+=( "${strings[$i]}" )
+done
+# output in normal or reverse order
+for (( i=0 ; i<${#result[@]} ; ++i)) ; do
+    [[ $reverse == n ]] && echo -n "$sep${result[i]}" || echo -n "$sep${result[~i]}"
+    sep=","
+done
+echo
+exit 0