Add solution #465

Author: JoshCrozier

README.md

@@ -453,6 +453,7 @@
 462|[Minimum Moves to Equal Array Elements II](./solutions/0462-minimum-moves-to-equal-array-elements-ii.js)|Medium|
 463|[Island Perimeter](./solutions/0463-island-perimeter.js)|Medium|
 464|[Can I Win](./solutions/0464-can-i-win.js)|Medium|
+465|[Optimal Account Balancing](./solutions/0465-optimal-account-balancing.js)|Hard|
 466|[Count The Repetitions](./solutions/0466-count-the-repetitions.js)|Hard|
 467|[Unique Substrings in Wraparound String](./solutions/0467-unique-substrings-in-wraparound-string.js)|Medium|
 468|[Validate IP Address](./solutions/0468-validate-ip-address.js)|Medium|

solutions/0465-optimal-account-balancing.js

@@ -0,0 +1,46 @@
+/**
+ * 465. Optimal Account Balancing
+ * https://leetcode.com/problems/optimal-account-balancing/
+ * Difficulty: Hard
+ *
+ * You are given an array of transactions transactions where
+ * transactions[i] = [fromi, toi, amounti] indicates that the person with ID = fromi
+ * gave amounti $ to the person with ID = toi.
+ *
+ * Return the minimum number of transactions required to settle the debt.
+ */
+
+/**
+ * @param {number[][]} transactions
+ * @return {number}
+ */
+var minTransfers = function(transactions) {
+  const balances = new Array(12).fill(0);
+
+  for (const [from, to, amount] of transactions) {
+    balances[from] -= amount;
+    balances[to] += amount;
+  }
+
+  const debts = balances.filter(balance => balance !== 0);
+  return helper(0, 0);
+
+  function helper(index, count) {
+    if (index === debts.length) return count;
+
+    if (debts[index] === 0) return helper(index + 1, count);
+
+    let minTransactions = Infinity;
+    const currentDebt = debts[index];
+
+    for (let i = index + 1; i < debts.length; i++) {
+      if (debts[i] * currentDebt < 0) {
+        debts[i] += currentDebt;
+        minTransactions = Math.min(minTransactions, helper(index + 1, count + 1));
+        debts[i] -= currentDebt;
+      }
+    }
+
+    return minTransactions;
+  }
+};