java - 我想使2D随机数数组出现错误: incompatible types: int cannot be converted to int[]

Question

import java.util.Random;
public class RandomNumbers { 
    public static void main(String[] args) {
        int[][] randomNumbers = new int[10][];
        Random rand = new Random();
        System.out.print("Array1: [ ");
        for (int i = 0; i < randomNumbers.length; i++) {
            int n = rand.nextInt(20) + 0;
            randomNumbers[i] = n;
        }
        for (int i = 0; i < randomNumbers.length; i++) {
            System.out.print(" "  + randomNumbers[i]) ;
        }
        System.out.print(" ]") ;
    }
}

Answer 1

这是你想要的:

代码:带有随机数Run的2D数组

import java.util.Random;

public class Array2D_random {
    public static void main(String[] args) {
        int[][] randomNumbers = new int[10][10];

        Random rand = new Random();

        System.out.println("Array1: \n[ ");

         // how to initialize two dimensional array in Java
        // using for loop

        for (int i = 0; i < randomNumbers.length; i++) { // loop for row
            for (int j = 0; j < randomNumbers[i].length; j++) { // loop for column
                int n = rand.nextInt(20) + 0;
                randomNumbers[i][j] = n;
            }
        }
        for (int i = 0; i < randomNumbers.length; i++) {
            System.out.print(" {");
            for (int j = 0; j < randomNumbers[i].length; j++) {
                System.out.print("  " + randomNumbers[i][j] + "   ");
            }
            System.out.print(" } ");
            System.out.println();
        }
        System.out.print(" ]");
    }
}