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HTML 

              
                <div class="mw-category">
    <div class="mw-category-group">
        <h3>A</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Auguste-Blanqui" title="Boulevard Auguste-Blanqui">Boulevard Auguste-Blanqui</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>B</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Barb%C3%A8s" title="Boulevard Barbès">Boulevard Barbès</a></li>
            <li><a href="/wiki/Boulevard_Beaumarchais" title="Boulevard Beaumarchais">Boulevard Beaumarchais</a></li>
            <li><a href="/wiki/Boulevard_de_l%27Amiral-Bruix" title="Boulevard de l'Amiral-Bruix">Boulevard de l'Amiral-Bruix</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>C</h3>
        <ul>
            <li><a href="/wiki/Boulevard_des_Capucines" title="Boulevard des Capucines">Boulevard des Capucines</a></li>
            <li><a href="/wiki/Boulevard_de_la_Chapelle" title="Boulevard de la Chapelle">Boulevard de la Chapelle</a></li>
            <li><a href="/wiki/Boulevard_de_Clichy" title="Boulevard de Clichy">Boulevard de Clichy</a></li>
            <li><a href="/wiki/Boulevard_du_Crime" title="Boulevard du Crime">Boulevard du Crime</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>H</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Haussmann" title="Boulevard Haussmann">Boulevard Haussmann</a></li>
            <li><a href="/wiki/Boulevard_de_l%27H%C3%B4pital" title="Boulevard de l'Hôpital">Boulevard de l'Hôpital</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>I</h3>
        <ul>
            <li><a href="/wiki/Boulevard_des_Italiens" title="Boulevard des Italiens">Boulevard des Italiens</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>M</h3>
        <ul>
            <li><a href="/wiki/Boulevard_de_la_Madeleine" title="Boulevard de la Madeleine">Boulevard de la Madeleine</a></li>
            <li><a href="/wiki/Boulevard_de_Magenta" title="Boulevard de Magenta">Boulevard de Magenta</a></li>
            <li><a href="/wiki/Boulevard_Montmartre" title="Boulevard Montmartre">Boulevard Montmartre</a></li>
            <li><a href="/wiki/Boulevard_du_Montparnasse" title="Boulevard du Montparnasse">Boulevard du Montparnasse</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>R</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Raspail" title="Boulevard Raspail">Boulevard Raspail</a></li>
            <li><a href="/wiki/Boulevard_Richard-Lenoir" title="Boulevard Richard-Lenoir">Boulevard Richard-Lenoir</a></li>
            <li><a href="/wiki/Boulevard_de_Rochechouart" title="Boulevard de Rochechouart">Boulevard de Rochechouart</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>S</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Saint-Germain" title="Boulevard Saint-Germain">Boulevard Saint-Germain</a></li>
            <li><a href="/wiki/Boulevard_Saint-Michel" title="Boulevard Saint-Michel">Boulevard Saint-Michel</a></li>
            <li><a href="/wiki/Boulevard_de_S%C3%A9bastopol" title="Boulevard de Sébastopol">Boulevard de Sébastopol</a></li>
            <li><a href="/wiki/Boulevard_de_Strasbourg" title="Boulevard de Strasbourg">Boulevard de Strasbourg</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>T</h3>
        <ul>
            <li><a href="/wiki/Boulevard_du_Temple" title="Boulevard du Temple">Boulevard du Temple</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>V</h3>
        <ul>
            <li><a href="/wiki/Boulevard_Voltaire" title="Boulevard Voltaire">Boulevard Voltaire</a></li>
        </ul>
    </div>
    <div class="mw-category-group">
        <h3>Z</h3>
        <ul>
            <li><a href="/wiki/Boulevard_de_la_Zone" title="Boulevard de la Zone">Boulevard de la Zone</a></li>
        </ul>
    </div>
</div>
!

CSS
!

JS 

              
                // 기본 변수

const people = [
	{ first: 'Albert', last: 'Einstein', year: 1879, passed: 1955 },
	{ first: 'Isaac', last: 'Newton', year: 1643, passed: 1727 },
	{ first: 'Galileo', last: 'Galilei', year: 1564, passed: 1642 },
	{ first: 'Marie', last: 'Curie', year: 1867, passed: 1934 },
	{ first: 'Johannes', last: 'Kepler', year: 1571, passed: 1630 },
	{ first: 'Nicolaus', last: 'Copernicus', year: 1473, passed: 1543 },
	{ first: 'Max', last: 'Planck', year: 1858, passed: 1947 },
	{ first: 'Katherine', last: 'Blodgett', year: 1898, passed: 1979 },
	{ first: 'Ada', last: 'Lovelace', year: 1815, passed: 1852 },
	{ first: 'Sarah E.', last: 'Goode', year: 1855, passed: 1905 },
	{ first: 'Lise', last: 'Meitner', year: 1878, passed: 1968 },
	{ first: 'Hanna', last: 'Hammarström', year: 1829, passed: 1909 },
	{ first: 'Sherlock', last: 'Holmes', year: 1854, passed: 1957 },
	{ first: 'John ', last: 'Watson', year: 1852, passed: 1929 },
];



// ===================================

// 1. filter()
// 1500년대에 태어난 인물만 새 배열로 만들자

const fiften = people.filter(person =>
    (person.year >=1500 && person.year <=1599)
);

console.log(fiften)




// ===================================

// 2. map()
// 인물의 성+이름을 합쳐 새 배열로 만들자

const fullNames = people.map(person =>
	(person.first + ' ' + person.last)
);

console.log(fullNames);



// ===================================

// 3. sort()
// 먼저 태어난 순대로 인물을 정렬하자

const ordered = people.sort((a,b)=>{
	if(a.year > b.year) {
		return 1;
	} 
	if (a.year < b.year) {
		return -1;
	}
	return 0;
})

console.log(ordered)



// ===================================

// 4. reduce()
// 인물들의 수명(..)을 합쳐보자

const totalYears = people.reduce((total, person)=>{
   return total + (person.passed - person.year)    
}, 0);
console.log(totalYears);




// ===================================

// 5. sort()
// 오래 산 순대로 인물을 정렬하자

const oldest = people.sort((a,b)=>{
	const a_lifeTime = a.passed - a.year;
	const b_lifeTime = b.passed - b.year;
	if(a_lifeTime > b_lifeTime) {
		return -1;
	}
	if(a_lifeTime < b_lifeTime) {
		return 1;
	}
	return 0;
});

console.log(oldest);


// ===================================

// 6. includes()
// 이름에 'de'가 들어가는 인물만 배열로 만들자

const category = document.querySelector(".mw-category");
const categoryLinks = Array.from(category.querySelectorAll("a"));
const categoryLinksText = categoryLinks.map(link=>link.textContent);
const result = categoryLinksText.filter(text=>text.includes('de'));
// const result = de.filter(text=>text.indexOf("de") !== -1); //ES5
console.log(result);


// ===================================

// 7. sort()
// 이름을 기준으로 알파벳순대로 정렬하자

const people2 = ['Beck, Glenn', 'Becker, Carl', 'Beckett, Samuel', 'Beddoes, Mick', 'Beecher, Henry', 'Beethoven, Ludwig', 'Begin, Menachem', 'Belloc, Hilaire', 'Bellow, Saul', 'Benchley, Robert', 'Benenson, Peter', 'Ben-Gurion, David', 'Benjamin, Walter', 'Benn, Tony', 'Bennington, Chester', 'Benson, Leana', 'Bent, Silas', 'Bentsen, Lloyd', 'Berger, Ric', 'Bergman, Ingmar', 'Berio, Luciano', 'Berle, Milton', 'Berlin, Irving', 'Berne, Eric', 'Bernhard, Sandra', 'Berra, Yogi', 'Berry, Halle', 'Berry, Wendell', 'Bethea, Erin', 'Bevel, Ken', 'Biden, Joseph', 'Biko, Steve', 'Billings, Josh', 'Biondo, Frank', 'Birrell, Augustine', 'Black, Elk', 'Blair, Robert', 'Blair, Tony', 'Blake, William', 'Holmes, Sherlock', 'Watson, John', 'kim, Anne'];

const alpha = people2.sort((lastOne, nextOne)=>{
	const aName = lastOne.split(', ');
	const bName = nextOne.split(', ');
	
  if (aName[1] > bName[1]) {
    return 1;
  }
  if (aName[1] < bName[1]) {
    return -1;
  }
  return 0;
});

console.table(alpha);


// ===================================
// 8. reduce()

const data = ['car', 'car', 'truck', 'truck', 'bike', 'walk', 'car', 'van', 'bike', 'walk', 'car', 'van', 'car', 'truck', 'pogostick'];
const transportation = data.reduce((all, current)=>{
	if (current in all){
			all[current] ++;
	}else{
		all[current] = 1;
	}
	return all;
},{});

console.log(transportation);
!
999px

Console