moar stuff

src/problems/element.ts

@@ -0,0 +1,29 @@
+const findPath = (element) => {
+    const path = [];
+    let current = element;
+
+    while (current.parentNode) {
+        const index = current.parentNode.children.indexOf(current);
+        path.push(index);
+        current = current.parentNode;
+    }
+
+    return path;
+}
+
+const walkPath = (root, path) => {
+    let current = root;
+
+    while (path.length) {
+        current = current.children[path.pop()];
+    }
+
+    return current;
+}
+
+const findElement = (root, element) => {
+    const path = findPath(element);
+    const foundIt = walkPath(root, path);
+
+    return foundIt;
+}

src/problems/lru.test.ts

@@ -1,7 +1,7 @@
 import assert from 'assert';
 import { LRU } from './lru';
 
-const cache = new LRU<string>();
+const cache = new LRU<string>(5);
 
 cache.set({ key: 'foo', value: 'bar' });
 cache.set({ key: 'bar', value: 'foo' });
@@ -22,3 +22,9 @@ assert.equal(cache.items.head.value.key, 'foo');
 cache.set({ key: 'abc123', value: 'my value' });
 assert.equal(cache.items.head.value.key, 'abc123');
 assert.equal(cache.size, 5);
+
+cache.set({ key: 'abc456', value: 'my last value' });
+assert.equal(cache.size, 5);
+assert.equal(cache.items.head.value.key, 'abc456');
+assert.equal(cache.cache.has('bar'), false);
+assert.equal(cache.cache.get('abc456').value.value, 'my last value')

src/problems/lru.ts

@@ -12,13 +12,16 @@ export class LRU<ValueType> {
     items: DoublyLinkedList<CacheItem<ValueType>>;
     cache: Map<string, DoublyLinkedListNode<CacheItem<ValueType>>> = new Map();
 
-    constructor() {
+    constructor(limit) {
         this.items = new DoublyLinkedList<CacheItem<ValueType>>();
+        this.limit = limit;
     }
 
     set(item: CacheItem<ValueType>) {
-        if (this.items.count > this.limit) {
-            this.items.deleteTail();
+        if (this.items.count + 1 > this.limit) {
+            const tail = this.items.deleteTail();
+            this.size -= 1;
+            this.cache.delete(tail.value.key)
         }
 
         this.items.prepend(item);

src/problems/moveElement.ts

@@ -0,0 +1,32 @@
+const paint = (start, elapsed, duration, animate) => {
+    if (elapsed < duration) {
+        animate(elapsed);
+        requestAnimationFrame((step) => paint(start, step - start, duration, animate));
+    }
+}
+
+const translate = (el, distance = 0, direction = 'X') => {
+    el.dataset.translate = el.dataset.translate || JSON.stringify({
+        X: distance,
+        Y: distance,
+    });
+    const saved = JSON.parse(el.dataset.translate);
+    saved[direction] = distance;
+    el.dataset.translate = JSON.stringify(saved);
+
+    el.style.transform = `translate${direction}(${saved[direction]}px)`;
+};
+
+const moveElement = (duration, distance, direction, element) => {
+    const onFrame = (
+        elapsed
+    ) => {
+        const progress = elapsed / duration;
+        const amount = progress * distance;
+
+        translate(element, Math.min(amount, duration), direction);
+    };
+
+    requestAnimationFrame((step) => paint(step, 0, duration, onFrame));
+}
+moveElement(10000, 750, 'X', button);