fix typo

README.md

@@ -197,15 +197,15 @@ The following command performs the basic (OCaml) type check (and normalization w
 
 The following command performs the basic type check (and normalization which convert code into A-normal form, converts LTLf formulae into symbolic regular language) for one interface of a given ADT implementation.
 
-    $ ./_build/default/bin/main.exe ri-ntype-check meta-config.json data/ri/FileSystem_Tree/add.ml
+    $ ./_build/default/bin/main.exe ri-ntype-check meta-config.json data/ri/FileSystem_Tree/init.ml
 
 By enable the `preprocess` option in the config file `meta-config.json`, **Marple** will print the result of preprocess: desugaring, basic type check, and normalization. The details can be found in [Configuration of Marple](#configuration-of-marple).
 
 **Requirements:** We use bold and colored printing in the command line, make sure your terminal supports escape sequences.
 
 For example,
 
-    $ ./_build/default/bin/main.exe ri-ntype-check meta-config.json data/ri/FileSystem_Tree/add.ml
+    $ ./_build/default/bin/main.exe ri-ntype-check meta-config.json data/ri/FileSystem_Tree/init.ml
 
 will print