diff --git a/sitou/src/C016_Leet.java b/sitou/src/C016_Leet.java
new file mode 100644
index 0000000000000000000000000000000000000000..f60c49daffb4f7d18a9c48961608af566979127b
--- /dev/null
+++ b/sitou/src/C016_Leet.java
@@ -0,0 +1,38 @@
+import java.util.Map;
+import java.util.Scanner;
+
+class C016_Leet {
+    public static void main(final String[] args) {
+        
+        final Map<Character, Character> leet = Map.of(
+            'A', '4',
+            'E', '3',
+            'G', '6',
+            'I', '1',
+            'O', '0',
+            'S', '5',
+            'Z', '2'
+        );
+        
+        final Scanner scan_str = new Scanner(System.in);
+        while (scan_str.hasNextLine()) {
+            String output_str = "";
+            for (Character c : scan_str.nextLine().toCharArray()) {
+                output_str+=leet.getOrDefault(c, c);
+            }
+            System.out.println(output_str);
+        }
+        scan_str.close();
+        
+        /*以下のようにもできるが、Mapの使い方を学びたかった
+        scan_str = scan_str
+            .replace("A","4")
+            .replace("E","3")
+            .replace("G","6")
+            .replace("I","1")
+            .replace("O","0")
+            .replace("S","5")
+            .replace("Z","2")
+        System.out.println(scan_str);*/
+    }
+}