第八次作业

1.定义长度位5的整型数组,输入他们的值,用冒泡排序后输出.

package ydy3;

import java.util.Scanner;

public class test3{

public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int[] a = new int[5];
int i, j;
int k;
Scanner input = new Scanner(System.in);
System.out.println("请输入5个整数:");
for (i = 0; i < 5; i++) {
a[i] = input.nextInt();
}
for (i = 0; i < a.length - 1; i++) {
for (j = 0; j < a.length - 1 - i; j++) {
if (a[j] > a[j + 1]) {
k = a[j];
a[j] = a[j + 1];
a[j + 1] = k;
}
}
}
System.out.println("冒泡排序:");
for (i = 0; i < a.length; i++) {
System.out.println(a[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 ydy3;

import java.util.Scanner;

public class test3{

public static void main(String[] args) {
Scanner a=new Scanner(System.in);
int[] b = { 34, 22, 35, 67, 45, 66, 12, 33 };
int k = -1;
System.out.println("输入一个数");
int c = a.nextInt();
for (int i = 0; i < b.length; i++) {
if (b[i] == c) {
k = i;
System.out.println("下标为" + i);
break;
}
}
if (k == -1) {
System.out.println("not found");
}
}
}

 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 ydy3;

import java.util.Scanner;

public class test3{

public static void main(String[] args) {

double[][] a = {{1.1,2.2,3.2,4.4},{6.6,7.7,8.8,9.9},{12.1,13.5,14.5,15.5},{16.5,17.8,18,19.4},{11.2,12.2,13.3,14.4}};
for(int i = 0;i < 5;i++) {
for(int k = 0;k < 4;k++) {
System.out.print(a[i][k]+" ");
}
System.out.println();
}
}
}