Someone

public class harmadik {

	public static void main(String[] args) {
		int n;
		int szam = 0;

		if (args.length == 0) {
			n = 10;
		} else {
			try {
				n = Integer.parseInt(args[0]);
			} catch (NumberFormatException e) {
				n = 10;
			}

		}

		//felepitjuk a tombot
		int a[][] = new int[n][];

		for (int i = 0; i < n; ++i) {
			a[i] = new int[i];
			for (int j = 0; j < i; ++j) {
				szam++;
				a[i][j] = szam;
			}
		}
		
		//kiiras
		for (int i=0;i<n;++i){
			for (int j=0;j<a[i].length;++j){
				System.out.print(a[i][j] + " ");
			}
			System.out.println();
		}
	}

}