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@ababup1192

ababup1192/GoodPair.java

Created April 12, 2020 11:40
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GoodPair.java
package org.abab;
import java.util.Objects;
public class GoodsPair {
public final String name1;
public final String name2;
public GoodsPair(String name1, String name2) {
this.name1 = name1;
this.name2 = name2;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
GoodsPair goodsPair = (GoodsPair) o;
return Objects.equals(name1, goodsPair.name1) &&
Objects.equals(name2, goodsPair.name2);
}
@Override
public int hashCode() {
return Objects.hash(name1, name2);
}
@Override
public String toString() {
return name1 + " " + name2;
}
}
Raw
Main.java
package org.abab;
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
// 配列は安全ではない→リストを使う。List<String> ListはジェネリックスでString型に。
// ArrayListっていう配列のようなリストに。で、左でStringを記述してるから右は省略可能。(ダイヤモンドリスト）
List<GoodsPair> tmpGoodsPairList = new ArrayList<>();
/* 購入者の入力ループ */
for (int i = 0; i < n; i++) {
int m = scanner.nextInt();
List<String> pList = new ArrayList<>();
/* 商品の入力ループ */
for (int j = 0; j < m; j++) {
pList.add(scanner.next());
}
for (int j = 0; j < m - 1; j++) {
for (int k = j + 1; k < m; k++) {
String name1 = pList.get(j).compareTo(pList.get(k)) < 0 ? pList.get(j) : pList.get(k);
String name2 = pList.get(j).compareTo(pList.get(k)) > 0 ? pList.get(j) : pList.get(k);
tmpGoodsPairList.add(new GoodsPair(name1, name2));
}
}
}
Map<GoodsPair, Integer> map = new HashMap<>();
for (GoodsPair goodsPair : tmpGoodsPairList) {
if (map.containsKey(goodsPair)) {
map.put(goodsPair, map.get(goodsPair) + 1);
} else {
map.put(goodsPair, 1);
}
}
Set<Integer> quantitySet = new LinkedHashSet<>(map.values());
List<Integer> quantities = new ArrayList<>(quantitySet);
quantities.sort(Comparator.comparingInt((i) -> -i));
for (Integer q : quantities) {
List<GoodsPair> goodsPairList = new ArrayList<>();
map.forEach((goodsPair, q2) -> {
if (q.equals(q2)) {
goodsPairList.add(goodsPair);
}
});
goodsPairList.sort((gp1, gp2) -> {
if (gp1.name1.compareTo(gp2.name1) != 0) {
return gp1.name1.compareTo(gp2.name1);
} else {
return gp1.name2.compareTo(gp2.name2);
}
});
for (GoodsPair goodsPair : goodsPairList) {
System.out.println(q + " " + goodsPair);
}
System.out.println("------");
}
}
}
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