ITSA-41次競賽(心得報數)

1號解法：

public class Main {
	public static void main(String argv[]) {
		Scanner input = new Scanner(System.in);
		int n = input.nextInt();

		for (int j = 0; j < n; j++) {
			int people = input.nextInt();
			int die = input.nextInt();

			ArrayList list = new ArrayList(people);
			for (int i = 0; i < people; i++) {
				list.add(i + 1);
			}
			int index = 0;
			for (int k = 0; k < people; k++) {
				if (list.size() == 1) {
					System.out.println(list.get(0));
					break;
				}
				index = (index + die - 1) % list.size();
				list.remove(index);
			}
		}
	}
}


2號解法：

public class Main {
	public static void main(String argv[]) {
		Scanner input = new Scanner(System.in);
		int n = input.nextInt();
		if (1 < n && n < 10) {
			for (int j = 0; j < n; j++) {
				int people = input.nextInt();
				int die = input.nextInt();

				ArrayList list = new ArrayList(people);
				for (int i = 0; i < people; i++) {
					list.add(i + 1);
				}
				int index = 0;
				int result = r(index, die, list);
				System.out.println(result);
			}
		}
	}

	private static int r(int index, int die, ArrayList list) {
		if (list.size() == 1) {
			return (int) list.get(0) ;
		}
		index = (index + die - 1) % list.size();
		list.remove(index);
		return r(index, die, list);
	}
}