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heap sort

Nov 19, 2022CodeCatch
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TrackerHeads Acronyms

Aug 30, 2024C S

1 like • 18 views

# Acronyms
## Computer Numerical Control (CNC)
- Typicalldfdfsdffdafdasgfdgfgfdfdafdasfdafda

React - Lifting State

Jan 25, 2023C S

1 like • 11 views

export const Main = () => {
const [title, setTitle] = useState('');
return (
<ChildComponent
title={title}
onChange={e => setTitle(e.target.value)}
/>
);
};
export const ChildComponent = ({ title, onChange }) => {
return (
<Box component="form" onSubmit={() => {}} noValidate mt={5}>
<TextField
fullWidth
id="title"
label="Title"
name="title"
autoComplete="title"
autoFocus
color="primary"
variant="filled"
InputLabelProps={{ shrink: true }}
value={title}
onChange={onChange}
/>
</Box>
);
};

copyString.js

Nov 8, 2023LeifMessinger

0 likes • 6 views

function copyString(text){
async function navigatorClipboardCopy(text){
if(document.location.protocol != "https:"){
return false;
}
return new Promise((resolve, reject)=>{
navigator.clipboard.writeText(text).then(()=>{resolve(true);}, ()=>{resolve(false);});
});
}
function domCopy(text){
if(!(document.execCommand)){
console.warn("They finally deprecated document.execCommand!");
}
const input = document.createElement('textarea');
input.value = text;
document.body.appendChild(input);
input.select();
const success = document.execCommand('copy');
document.body.removeChild(input);
return success;
}
function promptCopy(){
prompt("Copy failed. Might have ... somewhere. Check console.", text);
console.log(text);
}
function done(){
alert("Copied to clipboard");
}
navigatorClipboardCopy(text).catch(()=>{return false;}).then((success)=>{
if(success){
done();
}else{
if(domCopy(text)){
done();
}else{
promptCopy();
}
}
});
}

retryPromise.js

Oct 20, 2023LeifMessinger

0 likes • 18 views

//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 error
if (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 aValue
function 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 test
for(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 one
let 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 one
retryPromise(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 one
retryPromise(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 one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)

luhnCheck implementation

Nov 19, 2022CodeCatch

0 likes • 2 views

const luhnCheck = num => {
let arr = (num + '')
.split('')
.reverse()
.map(x => parseInt(x));
let lastDigit = arr.splice(0, 1)[0];
let sum = arr.reduce(
(acc, val, i) => (i % 2 !== 0 ? acc + val : acc + ((val *= 2) > 9 ? val - 9 : val)),
0
);
sum += lastDigit;
return sum % 10 === 0;
};
luhnCheck('4485275742308327'); // true
luhnCheck(6011329933655299); // true
luhnCheck(123456789); // false
function printHeap(heap, index, level) {
if (index >= heap.length) {
return;
}
console.log(" ".repeat(level) + heap[index]);
printHeap(heap, 2 * index + 1, level + 1);
printHeap(heap, 2 * index + 2, level + 1);
}
//You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0.
let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9];
printHeap(heap,0,0)