Zybooks?
0 likes • Oct 29, 2020 • 2 views
JavaScript
Loading...
More JavaScript Posts
class Timer{start(){this.startTime = Date.now();}stop(){const dt = Date.now() - this.startTime;console.log(dt);return dt;}getExecTime(fun, asynchronous){return asynchronous ? this.getAsyncExecTime(fun) : this.getSyncExecTime(fun);}getSyncExecTime(fun){this.start();fun();return this.stop();}async getAsyncExecTime(fun){this.start();await fun();return this.stop();}static average(fun, numTimes, asynchronous = false){const times = [];const promises = [];let timer = new Timer();if(asynchronous){for(let i = 0; i < numTimes; i++){timer.getAsyncExecTime(fun);}}else{for(let i = 0; i < numTimes; i++){timer.getSyncExecTime(fun);}}return (times => times.reduce(((sum, acc) => sume + acc), 0) / times.length);}static async timeAsync(fun, numTimes){if(numTimes <= 1) return new Timer().getAsyncExecTime(fun);const promises = [];let timer = new Timer(true);for(let i = 0; i < numTimes; i++){promises.push(fun().catch((e)=>{}));}try{await Promise.all(promises).catch((e)=>{});}catch(e){//do absolutely nothing}return timer.stop();}constructor(start = false){if(start) this.start();}}
const heapsort = arr => {const a = [...arr];let l = a.length;const heapify = (a, i) => {const left = 2 * i + 1;const right = 2 * i + 2;let max = i;if (left < l && a[left] > a[max]) max = left;if (right < l && a[right] > a[max]) max = right;if (max !== i) {[a[max], a[i]] = [a[i], a[max]];heapify(a, max);}};for (let i = Math.floor(l / 2); i >= 0; i -= 1) heapify(a, i);for (i = a.length - 1; i > 0; i--) {[a[0], a[i]] = [a[i], a[0]];l--;heapify(a, 0);}return a;};heapsort([6, 3, 4, 1]); // [1, 3, 4, 6]
const primes = num => {let arr = Array.from({ length: num - 1 }).map((x, i) => i + 2),sqroot = Math.floor(Math.sqrt(num)),numsTillSqroot = Array.from({ length: sqroot - 1 }).map((x, i) => i + 2);numsTillSqroot.forEach(x => (arr = arr.filter(y => y % x !== 0 || y === x)));return arr;};primes(10); // [2, 3, 5, 7]
const getTimezone = () => Intl.DateTimeFormat().resolvedOptions().timeZone;// ExamplegetTimezone();
class TreeNode {constructor(data, depth) {this.data = data;this.children = [];this.depth = depth;}}function buildNaryTree(hosts) {const nodeMap = {};// Step 1: Create a map of nodes using fqdn as the keyhosts.forEach((host) => {nodeMap[host.fqdn] = new TreeNode(host, 0); // Initialize depth to 0});// Step 2: Iterate through the array and add each node to its parent's list of childrenhosts.forEach((host) => {if (host.displayParent) {if (nodeMap[host.displayParent]) {const parent = nodeMap[host.displayParent];const node = nodeMap[host.fqdn];node.depth = parent.depth + 1; // Update the depthparent.children.push(node);} else {console.error(`Parent with fqdn ${host.displayParent} not found for ${host.fqdn}`);}}});// Find the root nodes (nodes with no parent)const rootNodes = hosts.filter((host) => !host.displayParent).map((host) => nodeMap[host.fqdn]);return rootNodes;}function treeToObjects(node) {const result = [];function inOrder(node) {if (!node) {return;}// Visit the current node and add it to the resultresult.push(node.data);// Visit children nodes firstnode.children.forEach((child) => {inOrder(child);});}inOrder(node);return result;}// Usage exampleconst hosts = [{fqdn: 'fqdn_1',display_name: 'Host 1',},{fqdn: 'fqdn_2',display_name: 'Host 2',displayParent: 'fqdn_1',},{fqdn: 'fqdn_3',display_name: 'Host 3'},{fqdn: 'fqdn_4',display_name: 'Host 4',displayParent: 'fqdn_3',},{fqdn: 'fqdn_5',display_name: 'Host 5',displayParent: 'fqdn_1',},];const tree = buildNaryTree(hosts);// Function to convert the tree to an array of objectsfunction convertTreeToArray(nodes) {const result = [];nodes.forEach((node) => {result.push(...treeToObjects(node));});return result;}// Convert the tree back to an array of objectsconst arrayFromTree = convertTreeToArray(tree);console.log(arrayFromTree);
const permutations = arr => {if (arr.length <= 2) return arr.length === 2 ? [arr, [arr[1], arr[0]]] : arr;return arr.reduce((acc, item, i) =>acc.concat(permutations([...arr.slice(0, i), ...arr.slice(i + 1)]).map(val => [item,...val,])),[]);};permutations([1, 33, 5]);// [ [1, 33, 5], [1, 5, 33], [33, 1, 5], [33, 5, 1], [5, 1, 33], [5, 33, 1] ]