约瑟夫环

public static int josheph(int x, int num) {
		// 数组初始化全为true
		boolean[] a = new boolean[x];
		for (int i = 0; i < x; i++) {
			a[i] = true;
		}
		
		int count = 0;
		int index = 0;
		int len = x;
		while (len > 1) {
			if (a[index] == true) {
				count++;
				if (count == num) {
					count = 0;
					a[index] = false;
					len--;
				}
			}
			index++;
			if (index == x) {
				index = 0;
			}
		}
		// 遍历找到最后一个为true的元素
		for (int i = 0; i < a.length; i++) {
			if (a[i]) {
				return i;
			}
		}
		return -1;
	}