收到错误消息 - “java.base/java.lang.StringConcatHelper.simpleConcat(StringConcatHelper.java:421)”

Question

大家好，我正在制作一个“生成所有括号”的程序，我收到错误消息：-"java.base/java.lang.StringConcatHelper.simpleConcat(StringConcatHelper.java:421) "

与此同时，我收到堆栈溢出错误

我正在附加一个包含此错误的代码，请查看它并在需要时告诉我修改：-

public class j{
public static void main(String[] args){
    int n = 2;
    int open = n;
    int close = n;
    String op = " ";
    findAns(op, open, close);
}
private static void findAns(String op, int open, int close){
    if (open == 0 && close == 0){
        System.out.println(op);
    }
    
    if (open == close){
        String op1 = op + "(";
        findAns(op1, open - 1, close);
        return;
    }
    if (open != 0){
        String op1 = op + "(";
        open = open - 1;
        findAns(op1, open, close);
    }
    String op1 = op + ")";
    close = close - 1;
    findAns(op1, open, close);
    return;
}   }

Answer 1

您的递归需要一个退出条件。也许是这个？

if (open == 0 && close == 0){
    System.out.println(op);
--> return;
}