add: 柠檬水找零

src/array/lemonade-change.js

@@ -0,0 +1,31 @@
+/**
+ * @param {number[]} bills
+ * @return {boolean}
+ */
+export const lemonadeChange = function (bills) {
+  const map = new Map()
+
+  while (bills.length) {
+    const money = bills.shift()
+
+    if (money === 5) {
+      map.set(5, (map.get(5) || 0) + 1)
+    } else {
+      let change = money - 5
+      while (change !== 0 && change - 10 > 0 && map.get(10) > 0) {
+        map.set(10, map.get(10) - 1)
+        change -= 10
+      }
+
+      while (change !== 0 && map.get(5) > 0) {
+        map.set(5, map.get(5) - 1)
+        change -= 5
+      }
+
+      if (change !== 0) return false
+      map.set(money, (map.get(money) || 0) + 1)
+    }
+  }
+
+  return true
+}