• Feb 21, 2025 •leafboo
0 likes • 3 views
console.log("hello world")
• Sep 13, 2023 •C S
0 likes • 11 views
/** * @param {number[]} nums * @return {number[]} */ var productExceptSelf = function(nums) { var output = []; var leftMult = 1; var rightMult = 1; for (var i=nums.length - 1; i >= 0; i--) { output[i] = rightMult; rightMult *= nums[i]; console.log({output: JSON.stringify(output), i}) } for (var j=0; j < nums.length; j++) { output[j] *= leftMult; leftMult *= nums[j]; console.log({output: JSON.stringify(output), j}) } return output; }; console.log(productExceptSelf([1, 2, 3, 4]))
• Nov 19, 2022 •CodeCatch
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const nums = [1, 2, 3]; const strs = Array.from('est'); nums.push(6); nums.push(4, 9); strs.unshift('t'); nums.length; // 6 nums[nums.length - 1]; // 9 strs[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); // 25 strs.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; // 5 nums.has(4); // true nums.delete(4); nums.has(4); // false [...nums]; // [1, 2, 3, 5] nums.clear(); nums.size; // 0 const items = new Map([ [1, { name: 'John' }], [2, { name: 'Mary' }] ]); items.set(4, { name: 'Alan' }); items.set(2, { name: 'Jeff' }); items.size; // 3 items.has(4); // true items.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
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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] ]
• Feb 3, 2021 •C S
0 likes • 2 views
import React, { useState } from 'react' import Welcome from '../components/Welcome' function About() { const [showWelcome, setShowWelcome] = useState(false) return ( <div> {showWelcome ? <Welcome /> : null} </div> <div> {showWelcome && <Welcome /> } </div> ) } export default App
function Welcome(props) { return <h1>Hello, {props.name}</h1>; } function App() { return ( <div> <Welcome name="Sara" /> <Welcome name="Cahal" /> <Welcome name="Edite" /> </div> ); } ReactDOM.render( <App />, document.getElementById('root') );