Added solutions for all 24 challanges

[PEluffy]

RESIDENTS: If you're attempting to make a pull request for your unit challenge, please ignore these instructions. You only need to submit a PR if you're attempting to update the main branch or if you're submitting an assessment.

Description

I have expanded the callbacks challenge section from 6-7 challenges solutions to 24.

I noticed the repo was missing many of the challenges discussed in the course,
so I have formalized them here to provide a more complete solutions.

Checklist

• I've added a descriptive title to this PR
• I've referenced an issue in Linear through including the issue ID in either the branch name or PR title
• I've tagged Marselena Sequoia as a reviewer

[Copilot]

Pull request overview

This pull request expands the callbacks challenge solutions from 6-7 challenges to a complete set of 24 challenges. The PR adds 18 new challenge solutions (Challenges 8-24) plus test cases, and modifies some existing challenges (Challenges 1-7) with implementation changes and uncommented test console.log statements.

Changes:

• Added 18 new challenge solutions covering advanced callback patterns including intersection, union, object filtering, piping, and functional composition
• Modified existing challenge implementations with refactored variable names and logic
• Uncommented all test console.log statements throughout the file

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[Copilot]

The variable name 'sumOfString' is misleading. It's used to accumulate values that are initially a string ('cat') but could be any type in general usage of a pipe function. Consider using a more generic name like 'accumulator' or 'result'.

Suggested change

	let sumOfString = value;
	for (let i = 0; i < arrOfFuncs.length; i++) {
	let callback = arrOfFuncs[i];
	sumOfString = callback(sumOfString);
	}
	return sumOfString;
	let accumulator = value;
	for (let i = 0; i < arrOfFuncs.length; i++) {
	let callback = arrOfFuncs[i];
	accumulator = callback(accumulator);
	}
	return accumulator;

[Copilot]

The function name 'myFunc' is not descriptive. Based on the implementation, this function finds the index of the first element that passes the callback test. Consider using a more descriptive name like 'findIndex' to better convey its purpose.

[Copilot]

These test console.log statements should be commented out. Following the repository convention, test console.log statements should remain commented so learners can uncomment them selectively for testing.

[Copilot]

This test console.log statement should be commented out. Following the repository convention, test console.log statements should remain commented so learners can uncomment them selectively for testing.

Suggested change

	console.log(combineOperations(0, [add100, divByFive, multiplyByThree])); // Should output 60 -->
	// console.log(combineOperations(0, [add100, divByFive, multiplyByThree])); // Should output 60 -->

[Copilot]

This test console.log statement should be commented out. Following the repository convention, test console.log statements should remain commented so learners can uncomment them selectively for testing.

Suggested change

	console.log(groupBy(decimals, floored)); // should log: { 1: [1.3], 2: [2.1, 2.4] }
	// console.log(groupBy(decimals, floored)); // should log: { 1: [1.3], 2: [2.1, 2.4] }

[Copilot]

These test console.log statements should be commented out. Following the repository convention, test console.log statements should remain commented so learners can uncomment them selectively for testing.

Suggested change

	console.log(rating(checks, 64)); // should log: 100
	console.log(rating(checks, 66)); // should log: 75
	// console.log(rating(checks, 64)); // should log: 100
	// console.log(rating(checks, 66)); // should log: 75

[Copilot]

This test console.log statement should be commented out. Following the repository convention, test console.log statements should remain commented so learners can uncomment them selectively for testing.

Suggested change

	console.log(pipe(capAddlowRepeat, "cat")); // should log: 'CATcatCATcat'
	// console.log(pipe(capAddlowRepeat, "cat")); // should log: 'CATcatCATcat'

[Copilot]

The variable names 'oddCount' and 'evenCount' are misleading. This function accepts a generic callback and should work with any boolean condition, not just odd/even checks. Consider using more generic names like 'trueCount' and 'falseCount' to reflect the actual behavior.

Suggested change

	let oddCount = 0;
	let evenCount = 0;
	for (let i = 0; i < array.length; i++) {
	if (callback(array[i])) {
	oddCount += 1;
	} else {
	evenCount += 1;
	}
	}
	return oddCount > evenCount ? true : false;
	let trueCount = 0;
	let falseCount = 0;
	for (let i = 0; i < array.length; i++) {
	if (callback(array[i])) {
	trueCount += 1;
	} else {
	falseCount += 1;
	}
	}
	return trueCount > falseCount ? true : false;