Add solution #3044

Author: JoshCrozier

README.md

@@ -2147,6 +2147,7 @@
 3039|[Apply Operations to Make String Empty](./solutions/3039-apply-operations-to-make-string-empty.js)|Medium|
 3042|[Count Prefix and Suffix Pairs I](./solutions/3042-count-prefix-and-suffix-pairs-i.js)|Easy|
 3043|[Find the Length of the Longest Common Prefix](./solutions/3043-find-the-length-of-the-longest-common-prefix.js)|Medium|
+3044|[Most Frequent Prime](./solutions/3044-most-frequent-prime.js)|Medium|
 3066|[Minimum Operations to Exceed Threshold Value II](./solutions/3066-minimum-operations-to-exceed-threshold-value-ii.js)|Medium|
 3068|[Find the Maximum Sum of Node Values](./solutions/3068-find-the-maximum-sum-of-node-values.js)|Hard|
 3105|[Longest Strictly Increasing or Strictly Decreasing Subarray](./solutions/3105-longest-strictly-increasing-or-strictly-decreasing-subarray.js)|Easy|

solutions/3044-most-frequent-prime.js

@@ -0,0 +1,68 @@
+/**
+ * 3044. Most Frequent Prime
+ * https://leetcode.com/problems/most-frequent-prime/
+ * Difficulty: Medium
+ *
+ * You are given a m x n 0-indexed 2D matrix mat. From every cell, you can create numbers
+ * in the following way:
+ * - There could be at most 8 paths from the cells namely: east, south-east, south, south-west,
+ *   west, north-west, north, and north-east.
+ * - Select a path from them and append digits in this path to the number being formed by
+ *   traveling in this direction.
+ * - Note that numbers are generated at every step, for example, if the digits along the path
+ *   are 1, 9, 1, then there will be three numbers generated along the way: 1, 19, 191.
+ *
+ * Return the most frequent prime number greater than 10 out of all the numbers created by
+ * traversing the matrix or -1 if no such prime number exists. If there are multiple prime
+ * numbers with the highest frequency, then return the largest among them.
+ *
+ * Note: It is invalid to change the direction during the move.
+ */
+
+/**
+ * @param {number[][]} mat
+ * @return {number}
+ */
+var mostFrequentPrime = function(mat) {
+  const m = mat.length;
+  const n = mat[0].length;
+  const frequency = new Map();
+  const directions = [[0, 1], [1, 1], [1, 0], [1, -1], [0, -1], [-1, -1], [-1, 0], [-1, 1]];
+
+  const isPrime = num => {
+    if (num <= 1) return false;
+    for (let i = 2; i * i <= num; i++) {
+      if (num % i === 0) return false;
+    }
+    return true;
+  };
+
+  for (let i = 0; i < m; i++) {
+    for (let j = 0; j < n; j++) {
+      for (const [dx, dy] of directions) {
+        let x = i;
+        let y = j;
+        let num = 0;
+        while (x >= 0 && x < m && y >= 0 && y < n) {
+          num = num * 10 + mat[x][y];
+          if (num > 10 && isPrime(num)) {
+            frequency.set(num, (frequency.get(num) || 0) + 1);
+          }
+          x += dx;
+          y += dy;
+        }
+      }
+    }
+  }
+
+  let maxFreq = 0;
+  let result = -1;
+  for (const [num, freq] of frequency) {
+    if (freq > maxFreq || (freq === maxFreq && num > result)) {
+      maxFreq = freq;
+      result = num;
+    }
+  }
+
+  return result;
+};