题目一
代码
import java.util.*;public class Main {public static void main(String[] args){Scanner input=new Scanner(System.in);String str=input.nextLine();//nextLine()方法遇到回车结束输入，next()遇到空格int[]a=new int[10];//用来计数a[0]=-1;for(int i=0;i<str.length();i++){if(str.charAt( i )=='0')a[0]++;else if(str.charAt( i )=='1')//charAt(i)获取字符方法a[1]++;else if(str.charAt( i )=='2')a[2]++;else if(str.charAt( i )=='3')a[3]++;else if(str.charAt( i )=='4')a[4]++;else if(str.charAt( i )=='5')a[5]++;else if(str.charAt( i )=='6')a[6]++;else if(str.charAt( i )=='7')a[7]++;else if(str.charAt( i )=='8')a[8]++;else if(str.charAt( i )=='9')a[9]++;else; }for(int i=0;i<10;i++){System.out.printf("%-2d",i);}System.out.println();for(int i=0;i<10;i++){System.out.printf("%-2d",a[i]);}}
}输入输出
1 23 53 87 90 12 15 89 0
0 1 2 3 4 5 6 7 8 9
1 3 2 2 0 2 0 1 2 2题目二
代码
import java.util.*;public class Main {public static void main(String[] args){Scanner input=new Scanner(System.in);int n=input.nextInt();int locks[]=new int[n];//动态初始化// 进行n轮循环for (int i = 1; i <= n; i++) {// 对每隔i把锁进行操作for (int j = i - 1; j < n; j += i) {// 如果锁的状态为关闭，则将其状态改为打开if (locks[j] == 0) {locks[j] = 1;}// 如果锁的状态为打开，则将其状态改为关闭else {locks[j] = 0;}}}int cnt=0;//记打开锁的个数for (int i = 0; i < n; i++) {if (locks[i] == 1) {cnt++; }}for (int i = 0; i < n; i++) {if (locks[i] == 1) {System.out.print(i+1);cnt--;if(cnt>0)System.out.printf(" ");}}}
}输入输出
8
1 4题目三
代码
import java.util.Arrays;
import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner input = new Scanner(System.in);int n = input.nextInt();int[] arr = new int[n]; for (int i = 0; i < n; i++) {arr[i] = input.nextInt();}if (isAscendingOrder(arr)) {System.out.println("The list is already sorted.");} else {System.out.println("The list is not sorted");Arrays.sort(arr);//排序方法参考的课件for(int i=0;i<n;i++){System.out.print(arr[i]);if(i<n-1)System.out.printf(" ");}System.out.println();}}public static boolean isAscendingOrder(int[] arr) {//函数声明方法参考网络for (int i = 1; i < arr.length; i++) {if (arr[i] < arr[i - 1]) {return false;}}return true;}
}
输入输出
8 10 1 5 16 61 9 11 1
The list is not sorted
1 1 5 9 10 11 16 61
题目四
代码
import java.util.Arrays;
import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner input = new Scanner(System.in);//数组1int n = input.nextInt();int[] arrN = new int[n]; for (int i = 0; i < n; i++) {arrN[i] = input.nextInt();}//数组2int m = input.nextInt();int[] arrM = new int[m]; for (int i = 0; i < m; i++) {arrM[i] = input.nextInt();}//合并到数组3int x = n + m;int[] arr = new int[x];//合并System.arraycopy(arrN, 0, arr, 0, n);//方法参考课件+CSDNSystem.arraycopy(arrM, 0, arr, n, m);//排序Arrays.sort(arr);//打印System.out.print("The merged list is ");for(int i = 0; i < x; i++){System.out.print(arr[i]);if(i<x-1)System.out.printf(" ");}}
}
输入输出
5 1 5 16 61 111 4 2 4 5 6
The merged list is 1 2 4 5 5 6 16 61 111
