연산자 exam

public class exam04 {

	public static void main(String[] args) {
		int a = 10; // a에 10을 대입
		int b = 3; // b에 3을 대입
		System.out.println(a+b);
		System.out.println(a-b);
		System.out.println(a*b);
		System.out.println(a/b);
		System.out.println(a%b);
	}

}

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public class exam05 {

	public static void main(String[] args) {
		int a = -1; // a에 -1을 대입합니다.
		int b = 2;  // b에 2를 대입합니다. 
		System.out.println(a);  //a를 출력합니다.
		System.out.println(-b); // b의 부호를 바꿔 출력합니다.
	}

}

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public class exam06 {

	public static void main(String[] args) {
		boolean a = true;
		boolean b = false;
		boolean c = !b;	        // b의 값을 반대로 바꾸어 대입합니다.
		System.out.println(a);  // true
		System.out.println(!a); // false
		
		System.out.println(b); // false
		System.out.println(c); // true
	}

}

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public class exam07 {

	public static void main(String[] args) {
		int a = 1;
		System.out.println(a); 		// 1
		
		a++; // a의 값을 1증가
		System.out.println(a); 		// 2
		System.out.println(++a);	// 3
		System.out.println(a++);	// 3
		System.out.println(a);  	// 4
		
	}

}

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public class exam08 {

	public static void main(String[] args) {
		int a = 10;
		int b = 20;
		int c = 30;
		
		System.out.println(a<b);
		System.out.println(a>b);
		System.out.println(a+b <= c);
		System.out.println(a+b >= c);
	}

}

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public class exam09 {

	public static void main(String[] args) {
		double a = 3.14;
		double b = 5.14;
		System.out.println(a == b);
		System.out.println(a != b);
		
		String c1 = "Hello JAVA!";
		System.out.println(c1.equals("Hello java!"));
		System.out.println(c1.equals("Hello JAVA!"));
	}

}

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public class exam10 {

	public static void main(String[] args) {
		int a = 10;
		System.out.println(5 < a && a < 15);
		System.out.println((5 < a && a < 15) && a % 2 == 0);
		
		a = 4;
		System.out.println((5 < a && a < 15) && a % 2 == 0);
		System.out.println((5 < a && a < 15) || a % 2 == 0);
	}

}

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public class exam11 {

	public static void main(String[] args) {
		int a = 15;
		int b = 5;
		System.out.println(a|b);
		System.out.println(a&b);
		System.out.println(a^b);
		
		System.out.println(a>>2);
		System.out.println(b<<4);
	}

}

>>	오른쪽 시프트	2로 나눈 효과
<<	왼쪽 시프트	2를 곱한 효과

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public class exam12 {

	public static void main(String[] args) {
		int age = 17;
		System.out.println(age > 19 ? "성인입니다":"청소년입니다.");
	}

}

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public class exam13 {

	public static void main(String[] args) {
		int a = 3;
		int b = 5;
		
		b = a;
		System.out.println(b);
		
		a += 1;
		System.out.println(a);
		a /= 2;
		System.out.println(a);
		a *= a;
		System.out.println(a);
	}

}

class A{}
class B extends A{}

public class exam14 {

	public static void main(String[] args) {
		A a = new A();
		B b = new B();
		
		System.out.println("a instanceof A : " + (a instanceof A));
		System.out.println("b instanceof A : " + (b instanceof A));
		System.out.println("a instanceof B : " + (a instanceof B));
		System.out.println("b instanceof B : " + (b instanceof B));
	}

}