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Flatten an array

Nov 19, 2022CodeCatch
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JWT Authentication

Mar 11, 2021C S

0 likes • 1 view

const jwt = require("jsonwebtoken");
const authToken = (req, res, next) => {
const token = req.headers["x-auth-token"];
try {
req.user = jwt.verify(token, process.env.ACCESS_TOKEN_SECRET);
next();
} catch (err) {
console.log(err.message);
res.status(401).json({ msg: "Error authenticating token" });
}
};
module.exports = authToken;

LeetCode Contains Duplicate

Sep 13, 2023C S

0 likes • 2 views

/**
* @param {number[]} nums
* @return {boolean}
*/
var containsDuplicate = function(nums) {
return new Set(nums).size !== nums.length
};

Horizontal legend (d3.js)

Dec 17, 2024shaiRos

0 likes • 2 views

const rectSize = 15; // Size of the color box
const spacing = 5; // Space between legend items
let legend = canvas.append('g').attr('class','chart-legend')
.attr('transform', `translate(${0}, ${height + 3})`);
// Sample data for the legend
const legendData = [
{ label: 'low', color: '#1f77b4' },
{ label: 'medium', color: '#ff7f0e' },
{ label: 'high', color: '#2ca02c' },
{ label: 'very high', color: '#2ca02c' }
];
legend.selectAll('g')
.data(legendData)
.join('g')
.attr('class', 'legend-item')
.each(function (d, i) {
const legendItem = d3.select(this);
console.log(d.label)
console.log(d.label?.length)
let labelWidth = (d.label.length * 5) + 7 + 15
var bbox = legendItem.node().getBBox()
var width = bbox.width
console.log(width)
// Add rectangle for color
legendItem.append('rect')
.attr('width', rectSize)
.attr('height', rectSize)
.attr('fill', d.color);
// Add label
legendItem.append('text')
.attr('x', rectSize + spacing) // Position text to the right of the rectangle
.attr('y', rectSize / 2) // Align text vertically with the rectangle
.attr('dy', '.35em') // Adjust vertical alignment
.attr('text-anchor', 'start') // Align text to the start
.text(d.label)
.attr('fill', 'black'); // Optional: Text color
// legendItem.attr('transform', `translate(${i * (rectSize + spacing + labelWidth)}, 0)`) // Position each item horizontally
});
const legendItems_spacing = 12
var legendLength = 0
legend.selectAll('.legend-item').each(function(d,i) {
d3.select(this).attr('transform',function() {
var bbox = d3.select(this).node().getBBox()
var width = bbox.width
// if (width == 0) width = (d.text.length * 5) +15 // not in dom yet
let startingPosition = 0
if (i > 0) {
startingPosition = legendLength
}
legendLength += width + legendItems_spacing
// return `translate(${xx - (width + 30)},0$)`
return `translate(${startingPosition},0)`
})
})

linked list

Nov 19, 2022CodeCatch

0 likes • 1 view

class LinkedList {
constructor() {
this.nodes = [];
}
get size() {
return this.nodes.length;
}
get head() {
return this.size ? this.nodes[0] : null;
}
get tail() {
return this.size ? this.nodes[this.size - 1] : null;
}
insertAt(index, value) {
const previousNode = this.nodes[index - 1] || null;
const nextNode = this.nodes[index] || null;
const node = { value, next: nextNode };
if (previousNode) previousNode.next = node;
this.nodes.splice(index, 0, node);
}
insertFirst(value) {
this.insertAt(0, value);
}
insertLast(value) {
this.insertAt(this.size, value);
}
getAt(index) {
return this.nodes[index];
}
removeAt(index) {
const previousNode = this.nodes[index - 1];
const nextNode = this.nodes[index + 1] || null;
if (previousNode) previousNode.next = nextNode;
return this.nodes.splice(index, 1);
}
clear() {
this.nodes = [];
}
reverse() {
this.nodes = this.nodes.reduce(
(acc, { value }) => [{ value, next: acc[0] || null }, ...acc],
[]
);
}
*[Symbol.iterator]() {
yield* this.nodes;
}
}
const list = new LinkedList();
list.insertFirst(1);
list.insertFirst(2);
list.insertFirst(3);
list.insertLast(4);
list.insertAt(3, 5);
list.size; // 5
list.head.value; // 3
list.head.next.value; // 2
list.tail.value; // 4
[...list.map(e => e.value)]; // [3, 2, 1, 5, 4]
list.removeAt(1); // 2
list.getAt(1).value; // 1
list.head.next.value; // 1
[...list.map(e => e.value)]; // [3, 1, 5, 4]
list.reverse();
[...list.map(e => e.value)]; // [4, 5, 1, 3]
list.clear();
list.size; // 0

Untitled

Apr 14, 2023Helper

0 likes • 8 views

const quickSort = arr => {
const a = [...arr];
if (a.length < 2) return a;
const pivotIndex = Math.floor(arr.length / 2);
const pivot = a[pivotIndex];
const [lo, hi] = a.reduce(
(acc, val, i) => {
if (val < pivot || (val === pivot && i != pivotIndex)) {
acc[0].push(val);
} else if (val > pivot) {
acc[1].push(val);
}
return acc;
},
[[], []]
);
return [...quickSort(lo), pivot, ...quickSort(hi)];
};
console.log(quickSort([1, 6, 1, 5, 3, 2, 1, 4])) // [1, 1, 1, 2, 3, 4, 5, 6]

unzipWith() function

Nov 19, 2022CodeCatch

0 likes • 0 views

const unzipWith = (arr, fn) =>
arr
.reduce(
(acc, val) => (val.forEach((v, i) => acc[i].push(v)), acc),
Array.from({
length: Math.max(...arr.map(x => x.length))
}).map(x => [])
)
.map(val => fn(...val));
unzipWith(
[
[1, 10, 100],
[2, 20, 200],
],
(...args) => args.reduce((acc, v) => acc + v, 0)
);
// [3, 30, 300]