added variable pointer start position

src/main.rs

@@ -6,8 +6,12 @@ mod turing;
 const LENGTH: usize = 64;
 
 fn main() {
+    // create turing machine
     let mut machine = TuringMachine::new();
 
+    // set pointer start position
+    machine.set_pointer(0);
+
     // config turing machine belt
     machine.set_belt(1, Value::Hash);
     machine.set_belt(2, Value::One);

src/turing.rs

@@ -57,6 +57,11 @@ impl TuringMachine {
         self.belt[index] = value;
     }
 
+    pub fn set_pointer(&mut self, index: usize) -> () {
+        // set pointer start position
+        self.pointer = index;
+    }
+
     pub fn set_transition(&mut self, state: u64, value: Value, next_state: u64) -> () {
         // If the State is not in the HashMap, add it
         if self.transitions.get(&state).is_none() {