java第六周作业

定义长度为5的整型数组,输入它们的值,用冒泡排序输出

package dome6_2sixweek_sunday;

import java.util.Scanner;

public class a {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int[] num = new int[5];
		Scanner input = new Scanner(System.in);
		for (int i = 0; i < num.length; i++) {
			System.out.print("请输入第" + (i + 1) + "个数:");
			num[i] = input.nextInt();
		}
		for (int i = 0; i < num.length - 1; i++) {
			for (int j = 0; j < num.length - 1 - i; j++) {
				if (num[j] > num[j + 1]) {
					int temp = num[j];
					num[j] = num[j + 1];
					num[j + 1] = temp;
				}
			}
		}
		for (int i = 0; i < num.length; i++) {
			System.out.print(num[i] + " ");
		}

	}

}

　　

定义数组{34,22,35,67,45,66,12,33},输入一个数a,查找在数组中是否存在,如果存在输出下标,不存在输出"not found" 

package demo6_2sixweek_sunday;

import java.util.Scanner;

public class b {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int i = 0;
		int a=0;
		int[] arr = { 34, 22, 35, 67, 45, 66, 12, 33 };
		Scanner input = new Scanner(System.in);

		System.out.print("请输入一个数字:");

		int n = input.nextInt();
		for (int j = 0; j < arr.length; j++) {
			if (n == arr[j]){
				i+=1;
			a=j;}
			else
				i+=2;
		}
		if(i%2!=0)
			System.out.println(a);
		else
			System.out.println("not found");
	}
}

　　

用矩阵输出一个double型的二维数组(长度分别为5,4,值自己定)的值

package dome6_2sixweek_sunday;

public class c {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		double[][] arr = { { 1, 2, 3, 4 }, { 5, 6, 7, 8 }, { 9, 8, 7, 6 }, { 5, 4, 3, 2 }, { 1, 2, 3, 4 } };
		for (int i = 0; i < arr.length; i++) {
			System.out.println();
			for (int j = 0; j < arr[i].length; j++) {
				System.out.print(arr[i][j] + "	");
			}
		}
	}

}

　　

定义一个二维数组(长度分别为3,4,值自己定),求该二维数组的最大值

package dome6_2sixweek_sunday;

public class d {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int[][] arr = { { 1, 2, 3, 4 }, { 5, 6, 7, 8 }, { 9, 8, 7, 6 } };
		int max = arr[0][0];

		for (int i = 0; i < arr.length; i++) {
			for (int j = 0; j < arr[i].length; j++) {
				if (arr[i][j] > max) {
					max = arr[i][j];
				}
			}
		}
		System.out.println("最大值为" + max);

	}

}