week1/Collatz.cs


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namespace ALGA {
	public class Collatz {
		public static int collatz_recursive(int n) {
			if (n <= 0) return -1;
			if (n == 1) return 0;
			if (n % 2 == 0) n /= 2;
			else n = n * 3 + 1;
			return 1 + collatz_recursive(n);
		}

		public static int collatz_iterative(int n) {
			if (n <= 0) return -1;
			if (n == 1) return 0;

			int steps = 0;
			while (n != 1) {
				if (n % 2 == 0) n /= 2;
				else n = n * 3 + 1;
				steps++;
			}
			return steps;
		}
	}
}