Set 應用

某家公司的面試題目：

import java.util.Set;
import java.util.TreeSet;
import java.util.Scanner;

public class SetDemo {
    public static void main(String[] args){
    
        Set<Integer> num = new TreeSet<>();
        Scanner scanner = new Scanner(System.in);
        Integer[] b = new Integer[3];
        for (int i = 0; i < 3 ;  i++){
            System.out.print("Please the eage's length: ");
            num.add(scanner.nextInt());
        }
        num.toArray(b);
        if (b[2] < (b[0]+b[1])){
        switch (num.size()){
            case 1: 
                System.out.println("正三角形");
                break;
            case 2:
                System.out.println("等腰三角形");
                break;
            case 3:
                if (triangle(b)){
                    System.out.println("直角三角形");
                } else {
                    System.out.println("其他種類三角形");
                }
        }
        } else {
             System.out.println("無法構成三角形");
        }
    }

    private static boolean triangle(Integer[] b) {
        if ((b[2] * b[2]) == (b[0]*b[0] + b[1]*b[1])){
          return true;
        } else {
            return false;
        }
    }
}