배열2(Day14)

package day15;

// 배열복사-예제 : 얕은 복사와 깊은 복사
public class day_15_01 {
	
	public static void main(String[] args) {
		int[] arr_a = {1,2,3,4};
		int[] arr_b = arr_a;	// 얕은 복사가 일어남.
		
		System.out.print("arr_b : ");
		for (int i = 0; i < arr_b.length; i++) {
			System.out.print(arr_b[i] + " ");
		}
		System.out.println();
		
		arr_a[0] = 99;
			
		System.out.printf("arr_b : ");
		for (int i = 0; i < arr_b.length; i++) {
			System.out.printf(arr_b[i] + " " );
		}
	}
}

package day15;

public class day_15_02 {
	public static void main(String[] args) {
		int[] oldIntArray = {1,2,3};	// 인덱스가 3개인 정수형 배열 선언
		int[] newIntArray = new int[5];	// 요소가 5개인 정수열 배열을 선언가지만 함
		
		System.out.print("oldIntArray : ");
		
		for (int i = 0; i < oldIntArray.length; i++) {
			System.out.print(oldIntArray[i] + " ");
		}
		System.out.println();
		
		for (int i = 0; i < oldIntArray.length; i++) {
			newIntArray[i] = oldIntArray[i];
		}
		System.out.print("newIntArray : ");
		for (int i = 0; i < newIntArray.length; i++) {
			System.out.print(newIntArray[i] + " ");
		}

		
	}
}

package day15;

public class day_15_03 {
	public static void main(String[] args) {
		String[] oldStrArray = {"java", "array", "copy"}; // 요소가 3인 문자열형 배열을 선언한 후,
														  // java, array, copy로 초기화함
		String[] newStrArray = new String[5];			  // 요소의 갯수가 5인 무자열형 배열을 선언만 함.
		
		System.out.print("oldStrArray : ");
		for (int i = 0; i < oldStrArray.length; i++) {
			System.out.print(oldStrArray[i] + " ");
		}
		System.out.println();
		
		System.arraycopy(oldStrArray, 0, newStrArray, 0, oldStrArray.length);
		System.out.print("newStrArray : ");
		
		for (int i = 0; i < newStrArray.length; i++) {
			System.out.print(newStrArray[i] + " ");
		}
		
	}
}

package day15;

public class day15_Ex01 {
	public static void main(String[] args) {
	
	// 얕은복사 예제
		
	int[] num1 = {92, 88, 91, 78, 89, 76, 99, 84, 91};
	int[] num2 = num1;
	
	System.out.print("num1 : ");
	for (int i = 0; i < num1.length; i++) {
		num2[i] = num1[i];
		System.out.print(num1[i] + " ");
	}
	System.out.println();
	
	num1[0] = 95;
	
	System.out.print("num2 : ");
	for (int i = 0; i < num1.length; i++) {
		System.out.print(num2[i] + " ");
	}
	}
}

package day15;

public class day15_Ex02 {
	public static void main(String[] args) {
	int[] num1 = {92, 89, 88, 91, 78, 89, 76, 99, 84, 91};
	int[] num2 = new int[10];
	
		
	System.out.print("num1 : ");
	for (int i = 0; i < num1.length; i++) {
		System.out.print(num1[i] + " ");
	}
	
	System.out.println();
	
	System.arraycopy(num1,0, num2,0, num2.length);
	// num1 0번부터 num2 0까지복사, num2.length의 개수만큼
	
	num1[0] = 55;
	
	System.out.print("num1-2 : ");
	for (int i = 0; i < num2.length; i++) {
		System.out.print(num1[i] + " ");
	}
	
	System.out.println("");
	
	System.out.print("num2 : ");
	for (int i = 0; i < num2.length; i++) {
		System.out.print(num2[i] + " ");
	}
  }
}

package day15;

public class day15_Ex03 {
	public static void main(String[] args) {
		
	int max = 0;
	
	int[] arr1 = {21,5,13,48,32};

	for (int i = 0; i < arr1.length; i++) {
		if (max < arr1[i]) {
			
			max = arr1[i];
		}
	}
	System.out.println("최대값 : " + max);
	
	
	}
}

package day15;

import java.util.Arrays;

public class day15_Ex04 {
	public static void main(String[] args) {

		int[] arr = { 20, 100, 50, 90, 10, 80, 30, 40, 60, 77 };

		System.out.println("정렬 전 ");

		System.out.println("=============================================");

		System.out.println(Arrays.toString(arr));

		final int length = arr.length;

		for (int i = 0; i < length; i++) {
			int min = i;
//
			for (int j = i + 1; j < length; j++) {

				if (arr[i] > arr[j]) {
					min = arr[j]; // 임시 변수 min을 이용하여
					arr[j] = arr[i];// arr[j]와 arr[i]의 값을
					arr[i] = min; // 서로 맞바꾼다.
				}
			}
		}

		System.out.println("정렬 후 ");

		System.out.println("=============================================");

		System.out.println(Arrays.toString(arr));

	}

}