Remove Sets From ArrayList
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Points:
10 (partial)
Time limit:
1.0s
Memory limit:
256M
Authors:
Problem type
Allowed languages
Java 19, Java 8
題目說明
請撰寫一個程式,先讀取五組字串,每個字串包含一到多個水果,水果之間以逗號分隔,水果可能重複。
程式應該將每一組存入HashSet
集合中,使得每一組都僅保留不重複的水果。再將這些集合存入一個ArrayList
陣列中。
程式另外讀取第六個字串,表示一個指定的水果,然後檢查陣列中的每個集合,若某個集合包含指定水果,則從陣列中移除該集合。
如果最後陣列不是空的,就輸出第一個集合和最後一個集合,輸出時會依照水果名稱排序(已實作在參考程式碼中的ShowSortedSet
函數)。如果最後陣列是空的,就僅輸出Empty
字樣。
可以利用以下的參考程式碼作為基礎,做小幅度的修改(可能在10
行以內),讓它可以滿足以上需求。若修改正確,當程式獲得以下每一組範例輸入時,應該產生該範例的對應輸出結果。
範例輸入#1
apple,banana,orange,pear
kiwi,grape,apple,kiwi
melon,peach,kiwi
banana,kiwi,apple,orange
grape,lemon,apple,banana,lemon
orange
範例輸出#1
apple,grape,kiwi
apple,banana,grape,lemon
範例輸入#2
mango,apple,blueberry
strawberry,orange,kiwi,grape
lemon,watermelon,apple
banana,pineapple,banana
peach,apple,blueberry,grape,orange
blueberry
範例輸出#2
grape,kiwi,orange,strawberry
banana,pineapple
範例輸入#3
mango,apple,blueberry
strawberry,orange,kiwi,grape,blueberry
lemon,watermelon,apple,blueberry,blueberry
banana,pineapple,banana,blueberry
peach,apple,blueberry,grape,orange
blueberry
範例輸出#3
Empty
參考程式碼
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Scanner;
public class MyProgram {
public static void main(String[] args) {
ArrayList<HashSet<String>> list = new ArrayList<>();
// Read input data, split by comma, and store in HashSet
Scanner scanner = new Scanner(System.in);
for (int i = 0; i < 5; i++) {
HashSet<String> set = new HashSet<>();
for (String value : scanner.nextLine().split(",")) {
set.add(value);
}
list.add(set);
}
// Read the value to remove
String valueToRemove = scanner.nextLine();
// Remove HashSet objects containing the specified value
removeSetsContainingValue(list, valueToRemove);
// Show the first and last elements of the list.
// The HashSet is shown as string, where the elements are sorted alphabetically.
if (list.isEmpty() == false) {
ShowSortedSet(list.get(0));
ShowSortedSet(list.get(list.size() - 1));
}
else {
System.out.println("Empty");
}
}
public static void ShowSortedSet(HashSet<String> set) {
ArrayList<String> sortedList = new ArrayList<>(set);
sortedList.sort(null);
System.out.println(String.join(",", sortedList));
}
}
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