/*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 study;
import java.util.*;
public class homework {
public static void main(String[] args) {
System.out.println("请输入五个数(用空格或者换行分隔开)：");
Scanner input=new Scanner(System.in);
int []a=new int[5];
int t=0;
for (int i = 0; i < a.length; i++) {
a[i]=input.nextInt();
}
for (int i = 0; i < a.length-1; i++) {
for (int j = 0; j < a.length-1-i; j++) {
if(a[j]>a[j+1]) {
t=a[j];
a[j]=a[j+1];
a[j+1]=t;
}
}
}
for (int i = 0; i < a.length; i++) {
System.out.print(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 study;
import java.util.*;
public class homework {
public static void main(String[] args) {
System.out.print("请输入一个数（查找它是否存在于数组中）：");
Scanner input=new Scanner(System.in);
int []a={34,22,35,67,45,66,12,33};
int t=input.nextInt();
int b=-1;
for (int i = 0; i < a.length; i++) {
if(t==a[i]) {
b=i;
}
}
if(b>-1) {
System.out.println("数组中存在，下标是："+b);
}else {
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。
*/
//错误提示：二维数组长度为5，4的定义为a[5][4],正确代码在页尾。
package study;
import java.util.*;
public class homework {
public static void main(String[] args) {
double[][] a= {{4.2,5.6,7.0,5.5,12.0},{1.2,6.5,7.9,85.6,4.8},
{8.88,41.2,12.3,5.3,1.11},{4.5,8.5,7.9,32.4,58.8}};
for (int i = 0; i < a.length; i++) {
for (int j = 0; j < 5; j++) {
System.out.print(a[i][j]+"\t");
}
System.out.print("\n");
}
}
}
/*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.
*/
//错误提示：二维数组长度为3，4的定义为a[3][4],正确代码在页尾。
package study;
import java.util.*;
public class homework {
public static void main(String[] args) {
double[][] a= {{4.2,5.6,7.0},{1.2,6.5,7.9},
{12.3,5.3,1.11},{7.9,32.4,58.8}};
double max1=0.0,max2=0.0;
for (int i = 0; i < a.length; i++) {
for (int j = 0; j < 3; j++) {
for (int h = j+1; h < 3; h++) {
if(a[i][j]>a[i][h]) {
max1=a[i][j];
}else {
max1=a[i][h];
}
}
}
if(max1>max2) {
max2=max1;
}
}
System.out.println(max2);
}
}
/*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。
*/
//更正：
package study;
import java.util.*;
public class homework {
public static void main(String[] args) {
double[][] a= {{4.2,5.6,7.0,5.5},{1.2,6.5,7.9,85.6},
{8.88,41.2,12.3,5.3},{4.5,8.5,7.9,32.4},{12.0,4.8,1.11,58.8}};
for (int i = 0; i < a.length; i++) {
for (int j = 0; j < 4; j++) {
System.out.print(a[i][j]+"\t");
}
System.out.print("\n");
}
}
}
/*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.
*/
//更正：
package study;
import java.util.*;
public class homework {
public static void main(String[] args) {
double[][] a= {{4.2,5.6,7.0,3.5},{1.2,6.5,7.9,7.8},
{12.3,5.3,1.11,99.9}};
double max1=0.0,max2=0.0;
for (int i = 0; i < a.length; i++) {
for (int j = 0; j < 4; j++) {
for (int h = j+1; h < 4; h++) {
if(a[i][j]>a[i][h]) {
max1=a[i][j];
}else {
max1=a[i][h];
}
}
}
if(max1>max2) {
max2=max1;
}
}
System.out.println(max2);
}
}
