Enock Omondi Trend20

People

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

	/*
	Prompt:
	We have defined a basic dropdown via the Dropdown and DropdownItem components below, with example usage
	in the ExampleNav component. The Dropdown and DropdownItem components have some problems, and also
	have room for improvements (doesn't everything?) A couple items TODO here (make sure to explain with comments!)

	0. How are you today? 😊
	1. Please fix any obvious issues you see with the dropdown.
	2. Please then make improvements to the dropdown and make it a bit more React-y. Assume this was cobbled
	together or brought in hastily from StackOverflow.

	function getMinDeletions(s) {
	const ordered_string = s.split('').sort().join('');
	let delCount = 0;

	for (let i = 0; i < ordered_string.length; i++) {
	if (ordered_string[i] === ordered_string[i + 1]) {
	delCount++;
	}
	}

	import { Directive, ElementRef, OnDestroy } from '@angular/core';
	import * as textMask from 'vanilla-text-mask/dist/vanillaTextMask.js';

	@Directive({
	selector: '[appMaskDate]'
	})
	export class MaskDateDirective implements OnDestroy {

	public mask = [/\d/, /\d/, '/', /\d/, /\d/, '/', /\d/, /\d/, /\d/, /\d/]; // dd/mm/yyyy
	public maskedInputController;