我不明白，为什么在本地IDEA上运行第三个测试点的数据，结果是正确的，但在洛谷上还是显示错误RE

import java.util.*;
public class Main {
    public static void main(String [] args){
        Scanner c=  new Scanner(System.in);
        int n = c.nextInt(); // n种操作
        String blank = c.nextLine(), s = c.nextLine();
        String str = s;
        while(n--!=0){
            int aa =c.nextInt();
            if(aa == 1){
                str = s.concat(c.nextLine().trim());
                System.out.println(str);
            }
            else if(aa == 2){
                int a = c.nextInt(), b = c.nextInt();
                str = str.substring(a, a+b);
                System.out.println(str);
                blank = c.nextLine();
            }
            else if(aa == 3){
                int a = c.nextInt();
                String cc = c.nextLine().trim();
                str = str.substring(0, a) + cc + str.substring(a);
                System.out.println(str);
            }
            else if(aa == 4){
                System.out.println(str.indexOf(c.nextLine().trim()));
            }
        }
    }
}