第6章 数组

6.1

package pra;
import java.util.Arrays;
public class Pra1 {
	public static void main(String[] args) {
		int arr1[]= {0,10,3,7,1,9};
		int arr2[]=Arrays.copyOf(arr1, 4);
		System.out.println("arr1:");
		for(int e:arr1) {
			System.out.print(e+" ");
		}
		System.out.println("\narr2:");
		for(int a:arr2) {
			System.out.print(a+" ");
		}			
	}
}

6.2

package pra;
public class Pra1 {
	public static void main(String[] args) {
		int arr[]= {10,3,7,1,9};
		int j=0;
		for(int i=0;i<arr.length-1;i++)
		{
			if(arr[i]<arr[i+1])
				j=arr[i];
			else
				j=arr[i+1];
		}
		System.out.println("数组arr中最小的值为"+j);
	}
}

6.3

package pra;
import java.util.Arrays;
public class Pra1 {
	public static void main(String[] args) {
		System.out.print("替换之前:");
		String arr[]= {"10","3","7","1","9"};
		for(String i:arr)
			System.out.print(i+" ");
		System.out.print("\n替换之后:");
		Arrays.fill(arr, 2,3,"bb");
		for(String i:arr)
			System.out.print(i+" ");
	}
}

6.4

package pra;
public class Pra1 {
	public static void main(String[] args) {
		int arr[][]=new int[][] {{1,2,3},{4,5,6},{7,8,9}};
		System.out.println("原数组:");
		for(int i[]:arr) {
			for(int j:i)
				System.out.print(j+" ");
			System.out.println("");
		}
		for(int i=0;i<arr.length;i++) {
			for(int j=i;j<arr[i].length;j++) {
				int temp=arr[i][j];
				arr[i][j]=arr[j][i];
				arr[j][i]=temp;
			}
		}
		System.out.println("行列互调后:");
		for(int i[]:arr) {
			for(int j:i)
				System.out.print(j+" ");
			System.out.println("");
		}
	}
}