feat: day 02, part 2 - not completed

Author: vicainelli

2024/ts/src/day-2-red-nosed-reports.test.ts

@@ -1,8 +1,10 @@
 import { describe, it, expect } from "bun:test";
 import {
   day_2_part_1,
+  day_2_part_2,
   isReportSafe,
   transformInputIntoArrays,
+  removeFirstNonSequential,
 } from "./day-2-red-nosed-reports";
 
 const fileTest = Bun.file("./src/day-2-red-nosed-reports.input.test.txt");
@@ -64,6 +66,44 @@ describe("transformInputIntoArrays", () => {
   });
 });
 
+describe("removeFirstNonSequential", () => {
+  it("return [7, 6, 4, 2, 1] for [7, 6, 4, 2, 1]", () => {
+    const result = removeFirstNonSequential([7, 6, 4, 2, 1]);
+    const expected = [7, 6, 4, 2, 1];
+    expect(result).toEqual(expected);
+  });
+  it("return [1, 2, 7, 8, 9] for [1, 2, 7, 8, 9]", () => {
+    const result = removeFirstNonSequential([1, 2, 7, 8, 9]);
+    const expected = [1, 2, 7, 8, 9];
+    expect(result).toEqual(expected);
+  });
+  it("return [9, 7, 6, 2, 1] for [9, 7, 6, 2, 1]", () => {
+    const result = removeFirstNonSequential([9, 7, 6, 2, 1]);
+    const expected = [9, 7, 6, 2, 1];
+    expect(result).toEqual(expected);
+  });
+  it("return [1, 2, 4, 5] for [1, 3, 2, 4, 5]", () => {
+    const result = removeFirstNonSequential([1, 3, 2, 4, 5]);
+    const expected = [1, 2, 4, 5];
+    expect(result).toEqual(expected);
+  });
+  it("return [8, 6, 4, 1] for [8, 6, 4, 4, 1]", () => {
+    const result = removeFirstNonSequential([8, 6, 4, 4, 1]);
+    const expected = [8, 6, 4, 1];
+    expect(result).toEqual(expected);
+  });
+  it("return [1, 3, 6, 7, 9] for [1, 3, 6, 7, 9]", () => {
+    const result = removeFirstNonSequential([1, 3, 6, 7, 9]);
+    const expected = [1, 3, 6, 7, 9];
+    expect(result).toEqual(expected);
+  });
+  it.skip("return [ 2, 4, 6, 9, 10] for [ 2, 4, 6, 9, 10, 9 ]", () => {
+    const result = removeFirstNonSequential([2, 4, 6, 9, 10, 9]);
+    const expected = [2, 4, 6, 9, 10];
+    expect(result).toEqual(expected);
+  });
+});
+
 describe("Day 2: Red-Nosed Reports", () => {
   describe("part 1", () => {
     it("should return the correct amount of report from the test file", () => {
@@ -79,4 +119,18 @@ describe("Day 2: Red-Nosed Reports", () => {
       expect(typeof contentTest).toBe("string");
     });
   });
+  describe("part 2", () => {
+    it("should return the correct amount of report from the test file", () => {
+      const result = day_2_part_2(contentTest);
+      const expected = 4;
+      expect(result).toBe(expected);
+      expect(typeof contentTest).toBe("string");
+    });
+    it.skip("should return the correct amount of report from the file", () => {
+      const result = day_2_part_2(content);
+      const expected = 307;
+      expect(result).toBe(expected);
+      expect(typeof contentTest).toBe("string");
+    });
+  });
 });

2024/ts/src/day-2-red-nosed-reports.ts

@@ -46,3 +46,66 @@ export const day_2_part_1 = (input: string): number => {
 
   return safeReports;
 };
+
+// ------ PART 2
+
+export function removeFirstNonSequential(arr) {
+  if (arr.length <= 2) return arr;
+
+  // Determine if sequence is ascending or descending
+  const isAscending = arr[1] > arr[0];
+  const result = [...arr];
+
+  // Find first number that breaks the sequence
+  for (let i = 1; i < arr.length - 1; i++) {
+    if (isAscending) {
+      // For ascending sequence, check current and next number
+      if (result[i] > result[i + 1]) {
+        result.splice(i, 1);
+        break;
+      }
+    } else {
+      // For descending sequence, check current and next number
+      // Also remove if numbers are equal (not strictly descending)
+      if (result[i] <= result[i + 1]) {
+        result.splice(i, 1);
+        break;
+      }
+    }
+  }
+
+  return result;
+}
+
+const removeConsecutiveDuplicates = (arr: number[]) =>
+  arr.filter((num, index) => num !== arr[index - 1]);
+
+// Check for consecutive duplicates
+const hasConsecutiveDuplicates = (arr: number[]) => {
+  return arr.some((num, index) => num === arr[index + 1]);
+};
+
+export const removingSingleBadLevel = (report: number[]): number[] => {
+  // find first duplicate, remove one of and return the new array
+
+  if (hasConsecutiveDuplicates(report))
+    return removeConsecutiveDuplicates(report);
+
+  return removeFirstNonSequential(report);
+};
+
+export const day_2_part_2 = (input: string): number => {
+  let safeReports = 0;
+
+  const reports = transformInputIntoArrays(input);
+
+  reports.map((report) => {
+    const changed_report = removingSingleBadLevel(report);
+
+    if (isReportSafe(changed_report)) {
+      safeReports += 1;
+    }
+  });
+
+  return safeReports;
+};