1.定义长度为5的整型数组,输入他们的值,用冒泡排序后输出
package pra; import java.util.Scanner; public class Text1 { public static void main(String[] args) { // TODO Auto-generated method stub int [] a = new int [5]; Scanner input = new Scanner(System.in); for (int i = 0; i < a.length; i++) { System.out.println("请输入第" + (i + 1) + "个数字"); a[i] = input.nextInt(); } for (int i = 0; i < a.length; i++) { for(int j = 0; j < a.length -1 -i; j++) { int num = 0; if(a[j] > a[j + 1]) { num = a[j]; a[j] = a[j + 1]; a[j + 1] = num; } } } for(int i : a) { System.out.print(i); } } }
2.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 pra; import java.util.Scanner; public class Text1 { public static void main(String[] args) { // TODO Auto-generated method stub int [] a = {34,22,35,67,45,66,12,33}; Scanner input = new Scanner(System.in); System.out.println("请输入要查找的数字"); int b = input.nextInt(); for (int i = 0; i < a.length; i++) { if(b == a[i]) { System.out.println("数字" + b + "的下标是:" + i); return; } } System.out.println("not found"); return; } }
3.以矩阵的形式输出一个double型二维数组(长度分别为5、4,值自己设定)的值
package pra; import java.util.Scanner; public class Text1 { public static void main(String[] args) { // TODO Auto-generated method stub double[][] a = {{5, 4, 8, 1}, {8, 9, 6, 3}, {5, 7, 1, 3}, {2, 4, 5, 7}, {6, 3, 9, 5}}; for (int i = 0; i < a.length; i++) { System.out.println(); for (int j = 0; j < a[i].length; j++) { System.out.print(a[i][j] + " "); } } } }
4.定义一个二维数组(长度分别为3,4,值自己设定),求该二维数组的最大值
package pra; import java.util.Scanner; public class Text1 { public static void main(String[] args) { // TODO Auto-generated method stub int[][] a = {{5, 4, 8, 10}, {8, 9, 6, 52}, {5, 7, 1, 140}}; int max = a[0][0]; for (int i = 0; i < a.length; i++) { for (int j = 0; j < a[i].length; j++) { if (a[i][j] > max) { max = a[i][j]; } } } System.out.println("最大值为" + max); } }