Day12

scripts/aoc2015/day12/puzzle1.ts

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+/*
+--- Day 12: JSAbacusFramework.io ---
+Santa's Accounting-Elves need help balancing the books after a recent order. Unfortunately, their accounting software uses a peculiar storage format. That's where you come in.
+
+They have a JSON document which contains a variety of things: arrays ([1,2,3]), objects ({"a":1, "b":2}), numbers, and strings. Your first job is to simply find all of the numbers throughout the document and add them together.
+
+For example:
+
+[1,2,3] and {"a":2,"b":4} both have a sum of 6.
+[[[3]]] and {"a":{"b":4},"c":-1} both have a sum of 3.
+{"a":[-1,1]} and [-1,{"a":1}] both have a sum of 0.
+[] and {} both have a sum of 0.
+You will not encounter any strings containing numbers.
+
+What is the sum of all numbers in the document?
+
+ */
+
+import { getNumbersFromText } from "./utils.ts";
+
+async function processFile(filename: string): Promise<number> {
+  // read the file string
+  const input = await Deno.readTextFile(filename);
+  const allNumbers = getNumbersFromText(input);
+  // sum all digits together
+  return allNumbers.reduce(
+    (accumulator: number, number: number) => accumulator + number,
+    0,
+  );
+}
+
+processFile("./simpleInput.txt").then((result) =>
+  console.log("result: ", result)
+);
+
+processFile("./input.txt").then((result) => console.log("result: ", result));

scripts/aoc2015/day12/puzzle2.ts

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+/*
+--- Part Two ---
+Uh oh - the Accounting-Elves have realized that they double-counted everything red.
+
+  Ignore any object (and all of its children) which has any property with the value "red". Do this only for objects ({...}), not arrays ([...]).
+
+  [1,2,3] still has a sum of 6.
+  [1,{"c":"red","b":2},3] now has a sum of 4, because the middle object is ignored.
+{"d":"red","e":[1,2,3,4],"f":5} now has a sum of 0, because the entire structure is ignored.
+  [1,"red",5] has a sum of 6, because "red" in an array has no effect.
+ */
+
+// read input
+// parseJson
+
+// let have a counter
+
+// sumNumbersOfObject:
+
+// if a value of object is "red" - return 0 for the object
+// if value is of type number - add it to counter
+// if value of object is array
+//    - sum all it's numbers
+//    - call all values of type object and sumNumberOfObject and sum them
+// if value of object is another object, transform it with sumNumbersOfObject
+
+import { sumNumbersOfObject } from "./utils.ts";
+
+async function processFile(filename: string): Promise<number> {
+  const input = await Deno.readTextFile(filename);
+  const o = JSON.parse(input);
+  return sumNumbersOfObject(o);
+}
+
+processFile("./input.txt").then((result) => {
+  console.log("result: ", result);
+});

scripts/aoc2015/day12/simpleInput.txt

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+{"a":{"b":4},"c":-1}

scripts/aoc2015/day12/utils.test.ts

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+import { describe, it } from "@std/testing/bdd";
+import { assertEquals } from "@std/assert";
+import { getNumbersFromText, sumNumbersOfObject } from "./utils.ts";
+
+describe("getNumbersFromText", () => {
+  it("should return empty array if text has no digits", function () {
+    assertEquals(getNumbersFromText("abc"), []);
+  });
+  it("should return array of numbers for text with numbers", function () {
+    assertEquals(getNumbersFromText("[1,-2,3]"), [1, -2, 3]);
+    assertEquals(getNumbersFromText(`{"a":2,"b":4}`), [2, 4]);
+    assertEquals(getNumbersFromText("[[[3]]]"), [3]);
+    assertEquals(getNumbersFromText(`{"a":{"b":4},"c":-1}`), [4, -1]);
+    assertEquals(getNumbersFromText(`{"a":[-1,1]}`), [-1, 1]);
+    assertEquals(getNumbersFromText(`[-1,{"a":1}]`), [-1, 1]);
+  });
+});
+
+describe("sumNumbersOfObject", () => {
+  it("should return 0 for empty object", function () {
+    assertEquals(sumNumbersOfObject({}), 0);
+  });
+  it("should return 3 for non-empty object", function () {
+    assertEquals(
+      sumNumbersOfObject({
+        a: 1,
+        b: 2,
+      }),
+      3,
+    );
+  });
+
+  it("should return count for object with array", function () {
+    assertEquals(
+      sumNumbersOfObject({
+        a: [1, 2],
+      }),
+      3,
+    );
+  });
+  it("should return 0 for object with 'red' value", function () {
+    assertEquals(
+      sumNumbersOfObject({
+        a: 3,
+        b: "red",
+      }),
+      0,
+    );
+  });
+  it("should return count for nested objects", function () {
+    assertEquals(
+      sumNumbersOfObject({
+        a: {
+          aa: 1,
+          ab: 2,
+        },
+      }),
+      3,
+    );
+  });
+  it("should return count for objects nested in arrays", function () {
+    assertEquals(
+      sumNumbersOfObject({
+        a: [1, 2, {
+          aa: 1,
+          ab: 2,
+        }],
+      }),
+      6,
+    );
+  });
+});

scripts/aoc2015/day12/utils.ts

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+const numbersRegex = /(-)?([0-9]+)/g;
+
+export function getNumbersFromText(text: string): number[] {
+  const result: number[] = [];
+  const allMatchesIterator = text.matchAll(numbersRegex);
+  for (const match of allMatchesIterator) {
+    const num = parseInt(match[0], 10);
+    if (!Number.isNaN(num)) {
+      result.push(num);
+    }
+  }
+  return result;
+}
+
+export function sumNumbersOfArray(arr: any[], count: number): number {
+  for (const item of arr) {
+    if (typeof item === "number") {
+      count = count + item;
+    } else if (Array.isArray(item)) {
+      count = sumNumbersOfArray(item, count);
+    } else if (typeof item === "object") {
+      count = sumNumbersOfObject(item, count);
+    }
+  }
+  return count;
+}
+
+export function sumNumbersOfObject(o: object, count = 0): number {
+  if (Object.values(o).find((v) => v === "red")) {
+    return count;
+  }
+  for (const value of Object.values(o)) {
+    if (typeof value === "number") {
+      count = count + value;
+    } else if (Array.isArray(value)) {
+      count = sumNumbersOfArray(value, count);
+    } else if (typeof value === "object") {
+      count = sumNumbersOfObject(value, count);
+    }
+  }
+  return count;
+}