在不带数组的Java中打印4行4列整数

public class PrintNumbers {
    public static void main(String[] args) {
        int rows = 4;
        int columns = 4;

        for (int i = 1; i <= rows; i++) {
            for (int j = 1; j <= columns; j++) {
                int number = (i - 1) * columns + j;
                System.out.print(number + " ");
            }
            System.out.println();
        }
    }
}

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