diff --git a/src/shunting_yard.rs b/src/shunting_yard.rs
index abef955..aac2f10 100644
--- a/src/shunting_yard.rs
+++ b/src/shunting_yard.rs
@@ -14,22 +14,21 @@ impl ShuntingYard {
 		}
 	}
 
-	fn is_operator(&mut self, value: char) -> bool {
+	fn is_shift_operator(&mut self, value: char) -> bool {
 		match value {
 			'&' | '^' | '|' => {
 				self.stack.push(value.to_string());
 				true
 			},
 			'>' | '<' => {
-				if let Some(last) = self.stack.last_mut() {
-					match last.as_str() {
+				match self.stack.last_mut() {
+					None => self.stack.push(value.to_string()),
+					Some(last) => match last.as_str() {
 						">" => *last = ">>".to_owned(),
 						"<" => *last = "<<".to_owned(),
 						_ => self.stack.push(value.to_string())
 					}
-				} else {
-					self.stack.push(value.to_string())
-				};
+				}
 				true
 			}
 			_ => false
@@ -40,7 +39,7 @@ impl ShuntingYard {
 		self.output = self.input.chars()
 			.collect::<Vec<char>>()
 			.into_iter()
-			.filter(|char| self.is_operator(*char))
+			.filter(|char| self.is_shift_operator(*char))
 			.map(|char_num| char_num.to_string())
 			.collect::<Vec<String>>();