Add solution #2352

Author: JoshCrozier

README.md

@@ -390,6 +390,7 @@
 2215|[Find the Difference of Two Arrays](./2215-find-the-difference-of-two-arrays.js)|Easy|
 2235|[Add Two Integers](./2235-add-two-integers.js)|Easy|
 2244|[Minimum Rounds to Complete All Tasks](./2244-minimum-rounds-to-complete-all-tasks.js)|Medium|
+2352|[Equal Row and Column Pairs](./2352-equal-row-and-column-pairs.js)|Medium|
 2390|[Removing Stars From a String](./2390-removing-stars-from-a-string.js)|Medium|
 2396|[Strictly Palindromic Number](./2396-strictly-palindromic-number.js)|Medium|
 2413|[Smallest Even Multiple](./2413-smallest-even-multiple.js)|Easy|

solutions/2352-equal-row-and-column-pairs.js

@@ -0,0 +1,34 @@
+/**
+ * 2352. Equal Row and Column Pairs
+ * https://leetcode.com/problems/equal-row-and-column-pairs/
+ * Difficulty: Medium
+ *
+ * Given a 0-indexed n x n integer matrix grid, return the number of pairs (ri, cj)
+ * such that row ri and column cj are equal.
+ *
+ * A row and column pair is considered equal if they contain the same elements in the
+ * same order (i.e., an equal array).
+ */
+
+/**
+ * @param {number[][]} grid
+ * @return {number}
+ */
+var equalPairs = function(grid) {
+  const columns = new Map();
+  let count = 0;
+
+  for (let i = 0; i < grid.length; i++) {
+    const column = [];
+    for (let j = 0; j < grid[i].length; j++) {
+      column.push(grid[j][i]);
+    }
+    columns.set(column.join(), (columns.get(column.join()) ?? 0) + 1);
+  }
+
+  for (let i = 0; i < grid.length; i++) {
+    count += columns.get(grid[i].join()) ?? 0;
+  }
+
+  return count;
+};