1.创建数组arr1和arr2将arr1中索引位置是0~3中的元素复制到数组arr2中并输出。
import java.util.Arrays;
public class HelloJava {
public static void main(String[] args) {
int arr1[] = new int[]{1,2,3,4,5};
int arr2[] = Arrays.copyOfRange(arr1, 0, 3);
for(int i : arr2) System.out.println(i);
}
}
2.将数组中最小的数输出
import java.util.Arrays;
public class HelloJava {
public static void main(String[] args) {
int arr1[] = new int[]{7,2,9,4,3,8};
Arrays.sort(arr1);
System.out.println(arr1[0]);
}
}
3.将数组arr中索引位置是2的元素替换为“bb”,输出数组替换前及替换后的所有元素。
import java.util.Arrays;
public class HelloJava {
public static void main(String[] args) {
String s[] = new String[] {"AB","UU","HAS","SAJ"};
for(String x:s)System.out.print(x+" ");
System.out.println();
Arrays.fill(s, 1,2,"bb");
for(String x:s)System.out.print(x+" ");
}
}
4.显示二维数组行列互调后的结果
public class HelloJava {
public static void main(String[] args) {
int a[][] = new int[][] {{1,2,3},{4,5,6},{7,8,9}};
for(int i=0;i<a.length;i++) {
for(int j=0;j<a[i].length;j++) System.out.print(a[i][j]);
System.out.println();
}
System.out.println();
for(int i=0;i<a.length;i++) {
for(int j=0;j<a[i].length;j++) System.out.print(a[j][i]);
System.out.println();
}
}
}