Leetcode/2870

README.md

@@ -231,3 +231,4 @@
 - [2131: Longest palindrome by concatenating two letter words](problems/leetcode/2131)
 - [2225: Find players with zero or one losses](problems/leetcode/2225) - Map
 - [2610: Convert an array into a 2d array with conditions](problems/leetcode/2610) - Medium - Array
+- [2870: Minimum number of operations to make array empty](problems/leetcode/2870)

problems/leetcode/2870/solution.js

@@ -0,0 +1,23 @@
+/**
+ * 
+ * @param {number[]} nums 
+ * @return {number}
+ */
+const minOperations = (nums) => {
+  const repsByNum = new Map();
+
+  for (const num of nums) {
+      repsByNum.set(num, (repsByNum.get(num) || 0) + 1);
+  }
+
+  let steps = 0;
+
+  for (const reps of repsByNum.values())  {
+      if (reps === 1) {
+          return -1;
+      }
+      steps += Math.ceil(reps / 3);
+  }
+
+  return steps;
+}