Add helper functions.

src/belt_finding/common.rs

@@ -1,3 +1,4 @@
+use core::panic;
 use std::io::Write;
 
 use base64::write;
@@ -68,6 +69,25 @@ impl Direction {
             Direction::Left => Direction::Down,
         }
     }
+
+    pub fn get_index(&self) -> u8 {
+        match self {
+            Direction::Up => 0,
+            Direction::Right => 1,
+            Direction::Down => 2,
+            Direction::Left => 3,
+        }
+    }
+
+    pub fn from_index(i: u8) -> Self {
+        match i {
+            0 => Direction::Up,
+            1 => Direction::Right,
+            2 => Direction::Down,
+            3 => Direction::Left,
+            _ => panic!(),
+        }
+    }
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]