day_7: part 2 done

src/advent_of_code/sat_07.rs

@@ -29,7 +29,7 @@ pub fn is_equation_true(equation: &Calibration) -> bool {
 }
 
 pub fn generate_operation_variants(count: usize) -> Vec<Vec<Operation>> {
-    let variants = vec![Operation::MUL, Operation::SUM];
+    let variants = vec![Operation::MUL, Operation::SUM, Operation::COMB];
     let variant_list: Vec<Vec<Operation>> = generate_combinations(&variants, count);
 
     variant_list
@@ -80,6 +80,11 @@ pub fn operate(
         Operation::MUL => {
             return first * second;
         }
+        Operation::COMB => {
+            return format!("{}{}", second, first)
+                .parse::<CalibrationResult>()
+                .unwrap()
+        }
     }
 }
 

src/advent_of_code/types.rs

@@ -55,4 +55,5 @@ pub struct Calibration(pub CalibrationResult, pub CalibrationEquation);
 pub enum Operation {
     SUM,
     MUL,
+    COMB,
 }