feat: day 04, part 1

Author: vicainelli

2024/ts/src/day-4-ceres-search.ts

@@ -0,0 +1,46 @@
+const input = `MMMSXXMASM
+MSAMXMSMSA
+AMXSXMAAMM
+MSAMASMSMX
+XMASAMXAMM
+XXAMMXXAMA
+SMSMSASXSS
+SAXAMASAAA
+MAMMMXMMMM
+MXMXAXMASX`;
+const table = input.split("\n").map((row) => row.split(""));
+const rows = table.length;
+const cols = table[0]?.length;
+const word = "XMAS".split("");
+let count = 0;
+
+for (let i = 0; i < rows; i++) {
+  for (let j = 0; j < rows; j++) {
+    // Find horizontal
+    const horizon = (idx: number) => table?.[i]?.[j + idx];
+    const horizonInv = (idx: number) => table?.[i]?.[j - idx];
+
+    if (word.every((char, idx) => char === horizon(idx))) count++;
+    if (word.every((char, idx) => char === horizonInv(idx))) count++;
+
+    // Find vertical
+    const vert = (idx: number) => table?.[i + idx]?.[j];
+    const vertInv = (idx: number) => table?.[i - idx]?.[j];
+
+    if (word.every((char, idx) => char === vert(idx))) count++;
+    if (word.every((char, idx) => char === vertInv(idx))) count++;
+
+    // Find diagonal
+    const diagTopLeft = (idx: number) => table?.[i + idx]?.[j + idx];
+    const diagTopRight = (idx: number) => table?.[i + idx]?.[j - idx];
+    const diagBottomLeft = (idx: number) => table?.[i - idx]?.[j + idx];
+    const diagBottomRight = (idx: number) => table?.[i - idx]?.[j - idx];
+
+    if (word.every((char, idx) => char === diagTopLeft(idx))) count++;
+    if (word.every((char, idx) => char === diagTopRight(idx))) count++;
+    if (word.every((char, idx) => char === diagBottomLeft(idx))) count++;
+    if (word.every((char, idx) => char === diagBottomRight(idx))) count++;
+  }
+}
+
+console.log(count);