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const express = require('express')const mongoose = require('mongoose')const cors = require('cors')const dotenv = require('dotenv')const server = express()dotenv.config()server.use(express.json())server.get('/' , (req , res)=>{res.send('Hello')})//4.lancement du serveurserver.listen(process.env.PORT , ()=>{console.log('server run on http://localhost:'+process.env.PORT)})
const bucketSort = (arr, size = 5) => {const min = Math.min(...arr);const max = Math.max(...arr);const buckets = Array.from({ length: Math.floor((max - min) / size) + 1 },() => []);arr.forEach(val => {buckets[Math.floor((val - min) / size)].push(val);});return buckets.reduce((acc, b) => [...acc, ...b.sort((a, b) => a - b)], []);};bucketSort([6, 3, 4, 1]); // [1, 3, 4, 6]
//Retries maxRetries number of times, meaning that if you have 0, then it'll run the function once.async function retryPromise(promiseFn, maxRetries = 3, delayOffset = 0, delayRandomRange = 0) {return new Promise((resolve, reject) => {promiseFn().then(resolve, (error) => { //On errorif (maxRetries <= 0) {return reject(error);} else {if(delayRandomRange * Math.random() + delayOffset < 1.0){return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolve, reject);}else{return new Promise((resolveTwo, rejectTwo) => {setTimeout(() => {return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolveTwo, rejectTwo);}, delayRandomRange * Math.random() + delayOffset);}).then(resolve, reject);}}});});}//Tests for that function.//Returns a function that will fail numTimes times, then will return aValuefunction functionThatReturnsAFunctionThatFailsACoupleTimes(numTimes, aValue){return async function(){if(numTimes == 0){return aValue;}numTimes--;throw false;};}const SMALL_NUMBER = 10;function testTest(failNumberOfTimes){let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(failNumberOfTimes, true);//Test my testfor(let i = 0; i < (failNumberOfTimes * 2); ++i){function evalTest(val){let testTestFailedReason = "";if(val === undefined){testTestFailedReason = "Test test returned undefined for some reason.";}if((i + 1) > failNumberOfTimes){if(val === true){//We're good}else{testTestFailedReason = "Test test didn't return true when it should have.";}}else{if(val === false){//We're good}else{testTestFailedReason = "Test test didn't return false when it should have.";}}testTestFailedReason = testTestFailedReason || "Test test passed test case";console.log(testTestFailedReason, "at index", i, "where the function returned", val);}functionThatFailsACoupleTimes().then(evalTest, evalTest)};}testTest(SMALL_NUMBER);let testCaseCounter = 1;const throwsNoError = [(val)=>{if(val == true){console.log("Passed test case " + (testCaseCounter++));}else{console.error("Unexpected return value", val);}},()=>{console.error("It wasn't supposed to fail!")}]const throwsError = [(val)=>{console.error("It wasn't supposed to succeed!", val);},(val)=>{if(val == false){console.log("Passed test case " + (testCaseCounter++));}else{console.error("Unexpected return value", val);}}];//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first onelet functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1).then(...throwsNoError)functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2).then(...throwsError)//Testing the delay. You'll have to wait a bit too.functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1, 500, 500).then(...throwsNoError)functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)
const shuffle = ([...arr]) => {let m = arr.length;while (m) {const i = Math.floor(Math.random() * m--);[arr[m], arr[i]] = [arr[i], arr[m]];}return arr;};const foo = [1, 2, 3];shuffle(foo); // [2, 3, 1], foo = [1, 2, 3]
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'));
const binarySearch = (arr, item) => {let l = 0,r = arr.length - 1;while (l <= r) {const mid = Math.floor((l + r) / 2);const guess = arr[mid];if (guess === item) return mid;if (guess > item) r = mid - 1;else l = mid + 1;}return -1;};binarySearch([1, 2, 3, 4, 5], 1); // 0binarySearch([1, 2, 3, 4, 5], 5); // 4binarySearch([1, 2, 3, 4, 5], 6); // -1