字符串最后一个长度

  public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        findlastword(s);
    }
    public static void findlastword(String s){
        String[] str = s.split(" ");
        int length  = str.length;
        System.out.println(str[length-1].length());
     }
}

计算字符个数

import java.util.Scanner;

/**
 * @author Liyongzhe
 * @date 2021/3/30_16:23
 */
public class huawei {
//写出一个程序，接受一个由字母、数字和空格组成的字符串，和一个字母，然后输出输入字符串中该字母的出现次数。不区分大小写。
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String store = sc.nextLine();
        String target = sc.nextLine();
        calculate(store,target);
    }

    private static void calculate(String store, String target) {
        char[] chars = store.toCharArray();
        int count = 0;
        for (int i = 0; i < chars.length; i++) {
           if (target.equalsIgnoreCase(String.valueOf(chars[i]))){
               count++;
           }
        }
        System.out.println(count);
    }

}

明明的随机数组

import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;

/**
 * @author Liyongzhe
 * @date 2021/3/30_16:23
 */
public class Main {

    //定义全局变量
    private static  Set<Integer> set = new TreeSet<Integer>();

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()){
            String store = sc.nextLine();
            int i = Integer.parseInt(store);
            output(i);
        }
    }

    //去重，升序
    private static void output(int i) {
        set.add(i);
        for (Integer integer : set) {
            System.out.println(integer);
        }
    }
}