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选择题

public class Test01 {
			
	public static void main(String[] args){
		System.out.println(new B().getValue());
		//1\new B()
		//2\.getValue()
		//16然后去getValue()
		//结果为：22、34、17
	}
	
	static class A{
		protected int value;
		public A(int v) {//5
			setValue(v);//调用的是子类重写的
		}
		public void setValue(int value){
			this.value = value;//10//22//16
		}
		public int getValue(){
			try{
				value++;//11//17
				return value;//11//17
			} catch(Exception e){
				System.out.println(e.toString());
			} finally {
				this.setValue(value);//调用的是子类重写的 11//调用的是子类重写的 17
				System.out.println(value);//22//34
			}
				return value;
		}
	}
	
	static class B extends A{
		public B() {
			super (5);
			setValue(getValue() - 3);//11-3 = 8//
		}
		public void setValue(int value){
			super.setValue(2 * value);//10//22//16//34
		}
	}
	
}

编程题

题目1

import java.util.Scanner;

public class Main {
	public static int gcd(int a,int b) {
		return a%b==0?b:gcd(b,a%b);
	}
	public static int lcm(int a,int b) {
		return (a*b)/gcd(a,b);
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		//先求最大公约数
		//int s1 = gcd(a,b);
		//再求最小公倍数
		int s2 = lcm(a,b);
		System.out.println(s2);
		sc.close();
	}
}

题目2

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
				
		String[] sum = new String[n];
		boolean f1 = false;
		boolean f2 = false;
		sc.nextLine();
		
		for(int i=0;i<n;i++) {
			String s = sc.next();
			sum[i] = s;
			//c
			//bb
			//aaa
			if(i>=1) {
				if(sum[i].length()>=sum[i-1].length()) {
					f1 = true;
				}else {
					f1 = false;					
				}
				if(sum[i].compareTo(sum[i-1])>=0) {
					f2 = true;
				}else {
					f2 = false;
				}
			}
		}
		if(f1 && !f2) {
			System.out.println("lengths");
			return ;
		}
		if(!f1 && f2) {
			System.out.println("lexicographically");
			return ;
		}
		if(f1 && f2) {
			System.out.println("both");
		}else {
			System.out.println("none");
		}
		sc.close();
	}
}