6, 9
2, 5
4, 6
how to initialize these number in an 2D array?
this is my answer, but something with output.
int[][] num = new int [3][2];
num[0][0] = 6;
num[0][1] = 9;
num[1][0] = 2;
num[1][1] = 5;
num[2][0] = 4;
num[2][1] = 6;
System.out.println(num);
[[I@70f87478 (output)
There's nothing wrong with that output, other than you're calling toString on array and expecting to get something useful. If you use Arrays.deepToString() instead, you'll get a more sensible result. (You'd normally only need Arrays.toString(), but you need the "deep" version as it's an array of arrays.)
Additionally, you can initialize the array more compactly. Combining the two:
import java.util.Arrays;
public class Test {
public static void main(String[] args) {
int[][] num = { { 6, 9 }, { 2, 5 }, { 4, 6 } };
System.out.println(Arrays.deepToString(num));
}
}
Output:
[[6, 9], [2, 5], [4, 6]]
int[][] num = {{6,9},{2,5},{4,6}}
System.out.println(Arrays.deepToString(num));
Logic like in deepToString
int [][] test = new int[1][1];
StringBuilder builder = new StringBuilder();
for (int[] ints : test) {
builder.append(Arrays.toString(ints));
}
System.out.println(builder.toString());
When you do
System.out.println(num);
You will print the object's default ´toString` method, which prints the object's reference. TO print the contents, you can use 2 nested for-loops or a for-each loop.