diff --git a/conf.pest b/conf.pest
index 67df1e6..3b8810b 100644
--- a/conf.pest
+++ b/conf.pest
@@ -1,3 +1,3 @@
-world = { ASCII_DIGIT* ~ " " ~ ASCII_DIGIT* }
-robot_init = { ASCII_DIGIT* ~ " " ~ ASCII_DIGIT* ~ " " ~ ("S" | "N" | "W" | "E") }
+world = { ASCII_DIGIT+ ~ " " ~ ASCII_DIGIT+ }
+robot_init = { ASCII_DIGIT+ ~ " " ~ ASCII_DIGIT+ ~ " " ~ ("S" | "N" | "W" | "E") }
 robot_instructions = { ASCII_ALPHA_UPPER+ }