2021-04-11

package com.company;

import java.sql.SQLOutput;

public class demo05 {

public static void main(String[] args) {

String s ="青春无悔";

        System.out.println(s.indexOf((int)'无'));

        System.out.println(s.indexOf("无"));

        System.out.println(s.lastIndexOf("春"));

    }

}