2017: Add day 1 part 2

2017/src/day01.spec.ts

@@ -19,4 +19,22 @@ describe('day 01', () => {
     expect(sum).toBe(1029)
   });
 
+  test('part 2', async () => {
+    const input = await readInput('day01-input.txt')
+    const captcha = input[0].split('').map(c => parseInt(c))
+
+    const forward = captcha.length / 2
+    const array = [...captcha, ...captcha]
+
+    const sum = captcha
+        .reduce((acc, it, idx) => {
+          if (it == array[idx+forward])
+            return acc + it
+          else
+            return acc
+        }, 0)
+
+    expect(sum).toBe(1220)
+  });
+
 });