这段代码无限运行，我不知道为什么它不起作用

Question

public class Main1
{
    public static void main(String[] args)
    {
        printNumbers(7, 3);
    }

    public static int printNumbers(int numValue, int rows) {
        for (int i = 0; i < rows; i++) {
            int x = (int)(Math.random() * 10);
            System.out.print(x);
            if (numValue == x && i < rows) {
                System.out.println(" ");
            } else if (i < rows) {
                System.out.print(x);
            }
        }
        return printNumbers(7, 3);
    }
}    

It's supposed to print random numbers until you reach the numValue, then it creates a new row, and there is a specified amount of rows. Although I put 3 rows, this code keeps running infinite rows. I must be missing something. I'm new to making methods and this is my first crack at it all by myself.

Answer 1

This method would recourse endlessly, as it unconditionally calls printNumbers(7,3) when it returns. From the looks of it, it doesn't seem you even need a return value there - change the return type to void , drop the return statement and you should be OK:

public static void printNumbers(int numValue, int rows){
    for (int i = 0; i < rows; i++) {
         int x = (int)(Math.random() * 10);
         System.out.print(x);
         if (numValue == x && i < rows) {
             System.out.println(" ");
         } else if (i < rows) {
           System.out.print(x);
         }
    }
}

Answer 2

Every recursive method should have a termination condition. I updated the same program to work correctly and it terminates the program when random numbers reach to numValue

public static void main(String[] args) {
    printNumbers(7, 3);
}

public static void printNumbers(int numValue, int rows) {
    for (int i = 0; i < rows; i++) {
        int x = (int) (Math.random() * 10);
        System.out.print(x);
        if (numValue == x && i < rows) {
            System.out.println(" ");
            return;
        } else if (i < rows) {
            System.out.print(x);
        }
    }
    printNumbers(7, 3);
}

//OUTPUT: 66003311997

Answer 3

There is no break/terminate condition in your recursion logic, this is causing your loop to run indefinitely.