fix: bug with unsorted dates

.gitignore

@@ -1 +1,2 @@
 node_modules
+.prettierrc

TypeScript/TollCalculator.test.ts

@@ -124,6 +124,15 @@ describe("TollCalculator", () => {
     expect(fee).toBe(16);
   });
 
+  test("It handles passing billings in unsorted order", () => {
+    const fee = tollCalculator.getTotalTollFee(Vehicle.Car, [
+      new Date(Date.UTC(1995, 11, 12, 9, 45)),
+      new Date(Date.UTC(1995, 11, 12, 8, 40)),
+    ]);
+
+    expect(fee).toBe(16);
+  });
+
   test("In case there are multiple billings in one hour, it only bills the largest one", () => {
     const fee = tollCalculator.getTotalTollFee(Vehicle.Car, [
       new Date(Date.UTC(1995, 11, 12, 8, 20)),

TypeScript/TollCalculator.ts

@@ -19,7 +19,7 @@ class TollCalculator {
     let tempFee = null;
     let totalFee = 0;
 
-    dates.forEach((date: Date) => {
+    dates.sort().forEach((date: Date) => {
       if (!this.isSameDay(date, startDate)) {
         throw "Billings must be in the same day.";
       }