2023.03

challenges/2023/03.js

@@ -0,0 +1,87 @@
+// Part 1
+const solvePuzzle1 = (input) => {
+  const map = input.split('\n').map((line) => line.split(''));
+  const alreadyCounted = [];
+  const numbers = [];
+
+  for (let y = 0; y < map.length; y++) {
+    for (let x = 0; x < map[0].length; x++) {
+      if (
+        !alreadyCounted.includes(`${y},${x}`) &&
+        getSurroundingCoordinates(y, x).some(([y, x]) => map[y]?.[x] && !/[\d.]/.test(map[y]?.[x]))
+      ) {
+        scanAndAdd(y, x, map, alreadyCounted, numbers);
+      }
+    }
+  }
+
+  return numbers.reduce((acc, num) => acc + Number(num), 0);
+};
+
+// Part 2
+const solvePuzzle2 = (input) => {
+  const map = input.split('\n').map((line) => line.split(''));
+  let sum = 0;
+
+  for (let y = 0; y < map.length; y++) {
+    for (let x = 0; x < map[0].length; x++) {
+      if (map[y][x] === '*') {
+        const alreadyCounted = [];
+        const numbers = [];
+
+        getSurroundingCoordinates(y, x).forEach(([y, x]) => {
+          scanAndAdd(y, x, map, alreadyCounted, numbers);
+        });
+
+        if (numbers.length === 2) {
+          sum += numbers[0] * numbers[1];
+        }
+      }
+    }
+  }
+  return sum;
+};
+
+const getSurroundingCoordinates = (y, x) => [
+  [y - 1, x],
+  [y - 1, x + 1],
+  [y, x + 1],
+  [y + 1, x + 1],
+  [y + 1, x],
+  [y + 1, x - 1],
+  [y, x - 1],
+  [y - 1, x - 1],
+];
+
+const scanAndAdd = (y, x, map, alreadyCounted, numbers) => {
+  if (!alreadyCounted.includes(`${y},${x}`) && /\d/.test(map[y]?.[x])) {
+    alreadyCounted.push(`${y},${x}`);
+
+    let currentNumber = map[y][x];
+
+    let xToLeft = x - 1;
+    let isNumberOnLeft = /[\d]/.test(map[y][xToLeft]);
+
+    while (isNumberOnLeft) {
+      alreadyCounted.push(`${y},${xToLeft}`);
+      currentNumber = map[y][xToLeft].concat(currentNumber);
+      xToLeft -= 1;
+      isNumberOnLeft = /[\d]/.test(map[y][xToLeft]);
+    }
+
+    let xToRight = x + 1;
+    let isNumberOnRight = /[\d]/.test(map[y][xToRight]);
+
+    while (isNumberOnRight) {
+      alreadyCounted.push(`${y},${xToRight}`);
+      currentNumber = currentNumber.concat(map[y][xToRight]);
+      xToRight += 1;
+      isNumberOnRight = /[\d]/.test(map[y][xToRight]);
+    }
+
+    numbers.push(Number(currentNumber));
+  }
+};
+
+require(__dirname + '/../../utils/test.js').test(__filename, __dirname, solvePuzzle1, '1');
+require(__dirname + '/../../utils/test.js').test(__filename, __dirname, solvePuzzle2, '2');