第八次作业
输出五个5个数长度为伍(10 20 30 40 50)数组来做
import java.util.Scanner; public class fewfw { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int []a={10,20,30,40,50}; for(int i=0;i<a.length;i++) System.out.println(a[i]); } }
将一个字符数组的值(neusofteducation)拷贝到另一个字符数组中。(知识点:数组复制) 必做题
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub String []a=new String[]{"n","e","u","s","o","f","t"}; String []b=new String[a.length]; System.arraycopy(a, 0, b, 0, a.length); for(int i=0;i<b.length;i++) { System.out.println(b[i]); } } }
给定一个有9个整数(1,6,2,3,9,4,5,7,8)的数组,先排序,然后输出排序后的数组的值。(知识点:Arrays.sort排序、冒泡排序)
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int[] a = { 1, 6, 2, 3, 9, 4, 5, 7, 8 }; 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]) { int temp = a[j]; a[j] = a[j + 1]; a[j + 1] = temp; } } } for (int i : a) { System.out.println(i); } } }
import java.util.Scanner; import java.util.Arrays; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int[] a = { 1, 6, 2, 3, 9, 4, 5, 7, 8 }; for (int i = 0; i <a.length - 1; i++) { for (int j = 0; j <a.length - 1 - i; j++) { } } Arrays.sort(a); for (int i : a) { System.out.println(i); } } }
输出一个double型二维数组(长度分别为5、4,值自己设定)的值。(知识点:数组定义和创建、多维数组初始化、数组遍历)
import java.util.Scanner; import java.util.Arrays; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub double a[][] = new double[5][4]; for (int i = 0; i <a.length; i++) { for (int j = 0; j < a[i].length; j++) { a[i][j] = i; } } 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(); } } }
在一个有8个整数(18,25,7,36,13,2,89,63)的数组中找出其中最大的数及其下标。(知识点:数组遍历、数组元素访问)
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int []a={18,25,7,36,13,2,89,63}; int max=a[0]; int c; int x; for ( c= 0; c <a.length; c++) { if(a[c]>max) max=a[c]; } x=c-1; System.out.println("最大值是"+max); System.out.println("下标是"+x); } }
.将一个数组中的元素逆序存放(知识点:数组遍历、数组元素访问)
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入数组中的元素个数"); int a = input.nextInt(); int b[] = new int[a]; System.out.println("输入数组元素:"); for (int i = 0; i < a; i++) { b[i] = input.nextInt(); } for (int j = a - 1; j > 0; j--) { System.out.print(b[j]); } System.out.println(b[0]); } }
将一个数组中的重复元素保留一个其他的清零。(知识点:数组遍历、数组元素访问)
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[] = new int[] { 6,9,8,2,5,7,7}; for (int i = 0; i < a.length; i++) { for (int j = 0; j < a.length; j++) { if (a[i] == a[j] && i != j) { a[j] = 0; } } } for (int x: a) { System.out.print(x); } } }
给定一维数组{ -10,2,3,246,-100,0,5},计算出数组中的平均值、最大值、最小值。(知识点:数组遍历、数组元素访问
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[] = new int[] { -10, 2, 3, 246, -100, 0, 5 }; int sum = 0; int max = a[0]; int min = a[0]; for (int i = 0; i < a.length; i++) { sum += a[i]; if (a[i] > max) max = a[i]; if (a[i] < min) min = a[i]; } int avg=sum/7; System.out.println("最大值是" + max); System.out.println("最小值是" + min); System.out.println("平均值是" + avg); } }
.使用数组存放裴波那契数列的前20项 ,并输出 1 1 2 3 5 8 13 21
import java.util.Scanner; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[] = new int[20]; a[0] = 1; a[1] = 1; for (int i = 2; i < a.length; i++) { a[i] = a[i - 1] + a[i - 2]; } for (int i = 0; i < 8; i++) { System.out.println(a[i]); } } }
生成一个长度为10的随机整数数组(每个数都是0-100之间),输出,排序后,再输出
import java.util.Scanner; import java.util.Arrays; import java.util.Random; public class wang123 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[]=new int[10]; Random x=new Random(); System.out.println("创建的100以内的随机数"); for (int i = 0; i < a.length; i++) { a[i]=x.nextInt(101); } for (int i = 0; i < a.length; i++) { System.out.println(a[i]); } System.out.println("经排序后 "); Arrays.sort(a); for (int i = 0; i < a.length; i++) { System.out.println(a[i]); } } }