约瑟夫出圈算法

public class Josephus {
	private int total;
	private int num;
	private int[] array;

	public Josephus(int total, int num) {
		this.total = total;
		this.num = num;
		array = new int[total];
		for (int i = 0; i < total; i++) {
			array[i] = i + 1;
		}
	}

	public static void main(String[] args) {
		Josephus josephus = new Josephus(20, 3);
		josephus.josephus();
	}

	public void josephus() {
		int i, j;

		if (this.getTotal() <= 0 || this.getNum() <= 0) //处理参数值不正确的情况
		{
			System.out.println("Paramter must bigger than zero!");
			return;
		}

		int k = 1; //标识处理第k个离开的人
		i = -1; //数组下标,下一个为0,即第一个人
		while (true) //k等于n表示只剩下一个人了
		{
			for (j = 0; j < this.getNum();) //在圈中数m个人
			{
				i = (i + 1) % this.getTotal();
				if (this.getArray()[i] > 0) {
					j++; //a[i] >0表示第i个人还没有离开
				}
			}
			if (k == this.getTotal()) {
				break;
			}
			System.out.println("No." + this.getArray()[i] + " is out!");
			this.getArray()[i] = -1; //表示该人离开
			k++;
		}
		System.out.println("No." + this.getArray()[i] + " is the winner!");
	}

	public int getTotal() {
		return total;
	}

	public void setTotal(int total) {
		this.total = total;
	}

	public int getNum() {
		return num;
	}

	public void setNum(int num) {
		this.num = num;
	}

	public int[] getArray() {
		return array;
	}

	public void setArray(int[] array) {
		this.array = array;
	}
}