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const arithmeticProgression = (n, lim) =>Array.from({ length: Math.ceil(lim / n) }, (_, i) => (i + 1) * n );arithmeticProgression(5, 25); // [5, 10, 15, 20, 25]
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);
// Time Complexity : O(N)// Space Complexity : O(1)var isMonotonic = function(nums) {let isMono = null;for(let i = 1; i < nums.length; i++) {if(isMono === null) {if(nums[i - 1] < nums[i]) isMono = 0;else if(nums[i - 1] > nums[i]) isMono = 1;continue;}if(nums[i - 1] < nums[i] && isMono !== 0) {return false;}else if(nums[i - 1] > nums[i] && isMono !== 1) {return false;}}return true;};let nums1 = [1,2,2,3]let nums2 = [6,5,4,4]let nums3 = [1,3,2]console.log(isMonotonic(nums1));console.log(isMonotonic(nums2));console.log(isMonotonic(nums3));
router.post("/", async (req, res) => {const { email, password } = req.body;try {if (!email) return res.status(400).json({ msg: "An email is required" });if (!password)return res.status(400).json({ msg: "A password is required" });const user = await User.findOne({ email }).select("_id password");if (!user) return res.status(400).json({ msg: "Invalid credentials" });const match = await bcrypt.compare(password, user.password);if (!match) return res.status(400).json({ msg: "Invalid credentials" });const accessToken = genAccessToken({ id: user._id });const refreshToken = genRefreshToken({ id: user._id });res.cookie("token", refreshToken, {expires: new Date(Date.now() + 604800),httpOnly: true,});res.json({ accessToken });} catch (err) {console.log(err.message);res.status(500).json({ msg: "Error logging in user" });}});
const nums = [1, 2, 3];const strs = Array.from('est');nums.push(6);nums.push(4, 9);strs.unshift('t');nums.length; // 6nums[nums.length - 1]; // 9strs[0]; // 't'strs[2]; // 's'nums.slice(1, 3); // [2, 3]nums.map(n => n * 2); // [2, 4, 6, 12, 8, 18]nums.filter(n => n % 2 === 0); // [2, 6, 4]nums.reduce((a, n) => a + n, 0); // 25strs.reverse(); // ['t', 's', 'e', 't']strs.join(''); // 'test'const nums = new Set([1, 2, 3]);nums.add(4);nums.add(1);nums.add(5);nums.add(4);nums.size; // 5nums.has(4); // truenums.delete(4);nums.has(4); // false[...nums]; // [1, 2, 3, 5]nums.clear();nums.size; // 0const items = new Map([[1, { name: 'John' }],[2, { name: 'Mary' }]]);items.set(4, { name: 'Alan' });items.set(2, { name: 'Jeff' });items.size; // 3items.has(4); // trueitems.get(2); // { name: 'Jeff' }items.delete(2);items.size; // 2[...items.keys()]; // [1, 4][...items.values()]; // [{ name: 'John' }, { name: 'Alan' }]items.clear();items.size; // 0
const levenshteinDistance = (s, t) => {if (!s.length) return t.length;if (!t.length) return s.length;const arr = [];for (let i = 0; i <= t.length; i++) {arr[i] = [i];for (let j = 1; j <= s.length; j++) {arr[i][j] =i === 0? j: Math.min(arr[i - 1][j] + 1,arr[i][j - 1] + 1,arr[i - 1][j - 1] + (s[j - 1] === t[i - 1] ? 0 : 1));}}return arr[t.length][s.length];};levenshteinDistance('duck', 'dark'); // 2