JavaScript Set and Map

 // ES6: Sets and Maps

// Sets
const certifications = new Set([
	'Admin', 'PD I', 'PD II', 'Admin', 'AppBuilder'
]);
console.log(certifications);
console.log(certifications.size); // It should be size not length

// Verify value 
console.log(certifications.has('Admin'));
console.log(certifications.has('Sales Cloud'));

// Adding Values
certifications.add('Salesforce CPQ')
console.log(certifications);

// Deleting values 
certifications.delete('Salesforce CPQ')
console.log(certifications);

// Iteration 
for(const cer of certifications) console.log(cer);

// Clear all the values 
certifications.clear();
console.log(certifications);

// *** Making Array as Set with the unique values 
const names = ['Mark', 'Steve', 'Mark', 'Bob'];
const uniqueNames = [...new Set(names)];
console.log(uniqueNames);

// size of array with unique values 
console.log(new Set(['Mark', 'Steve', 'Mark', 'Bob']).size);

// Size of a string with unique characters
console.log(new Set('Steve').size);
--Maps----------------
// Maps are like objects but map keys can be any data type (object keys always should be string)

const resMap = new Map();
resMap.set('firstName', 'Srinu');
resMap.set(1, 'Admin');
console.log(resMap.set(2, 'Dev'));

resMap
	.set('certifications',['Admin','PD I'])
	.set('city','Bangalore')
	.set(true,'He is a Trainer.');

console.log(resMap.get('firstName'));
console.log(resMap.get(resMap.get('firstName') === 'Srinu'));

console.log(resMap.has('lastName'));
resMap.delete('city');
console.log(resMap);
console.log(resMap.size);
resMap.clear();
console.log(resMap);

// resMap.set([1,2],'nums'); // won't work

// console.log(resMap.get([1,2])); // won't work

const myArr = [1,2];
resMap.set(myArr,'nums');
console.log(resMap.get(myArr));

// Map Iteration (Map entries are set of arrays)
const question = new Map([
	['question', 'Which is the #1 CRM Platform?'],
	[1, 'Microsoft'],
	[2, 'Salesforce'],
	[3, 'Zoho'],
	['correct', 2],
	[true, 'Correct'],
	[false, 'Try Again']
]);
console.log(question);

const workTimings = {
	tue : {
		startTime : 0,
		endTime : 8,
	},
	wed : {
		startTime : 8,
		endTime : 4,
	},
	thu : {
		startTime : 8,
		endTime : 4,
	},
	fri : {
		startTime : 8,
		endTime : 4,
	}
};

// Converting Object to map 
console.log(Object.entries(workTimings));
const timingsMap = new Map(Object.entries(workTimings));
console.log(timingsMap);

// Question Iteration 
console.log(question.get('question'));
for(const [key,value] of question) {
	if(typeof key === 'number') console.log(`Answer ${key}: ${value}`);
}

//const answer = Number(prompt('Enter Answer'));
const answer = 2;
console.log(answer);

console.log(question.get(question.get('correct') === answer));

// convert map to array
console.log([...question]);
console.log([...question.keys()]);
console.log([...question.values()]);

--When to choose which collection -----------------------
Data Structures -
	1. Arrays or Sets --> Simple List 
	2. Objects or Maps --> Key/Value Pair
	
	* Set is faster than Array 
	* Map is faster than Object 
	* For Json we use objects