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package exercise;
import java.util.Arrays;
public class Ex13_4_1 {
    public static void main(String[] args) {
        String[] words = {"book","paper","book","pencil","note","eraser"};
        Arrays.sort(words);
        for(String s : words) {
            System.out.println(s);
        }
    }
}

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package exercise;
import java.util.Arrays;
import lib.Input;
public class Ex13_4_2 {
    public static void main(String[] args) {
        String[] words = {"book","paper","book","pencil","note","eraser"};
        Arrays.sort(words);
        String key = Input.getString();
        int index = Arrays.binarySearch(words, key);
        System.out.println("検索結果=" + index);
    }
}

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package exercise;
import java.util.Arrays;
public class Ex13_4_3 {
    public static void main(String[] args) {
        String[] words = {"book","paper","book","pencil","note","eraser"};
        Arrays.stream(words)
               .distinct()
               .sorted()
               .forEach(w->System.out.println(w));
    }
}

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package exercise;
import java.util.Arrays;
public class Ex13_4_4 {
    public static void main(String[] args) {
        double[] data = new double[5];
        Arrays.fill(data, 5.1);
        double[] dataCopy = Arrays.copyOf(data, 10);
        System.out.println(Arrays.toString(dataCopy));
    }
}

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package exercise;
import java.util.Arrays;
public class Ex13_4_5 {
    public static void main(String[] args) {
        double[] data={2.8, -3.3,1.5, -5.2, 4.2, 8.1};
        double total = Arrays.stream(data)
                              .filter(d->d>0)
                              .sum();
        System.out.println("合計＝" + total);
    }
}