java实现斐波那契数列和约瑟夫环

斐波那契数列的递归实现：

public int fn(int n) {

if (n == 1 || n == 2)

return 1;

return fn(n-1)+fn(n-2);

}

非递归写法：

public int fn(int n) {

int a =1;

int b = 1;

int tmp;

if (n == 1 || n == 2)

return 1;

for (int i = 2; i < n; i++) {

tmp = a +b;

a = b;

b = tmp;

}

return b;

}

约瑟夫环找到一种简单的方法：

public class JosephRing {

public JosephRing(){};

public void cac(int m, int n) {

List<Integer> ls = new ArrayList<Integer>();

for (int i = 1; i <= n; i++)

ls.add(i);

int count = 0;

for (int i = 1; i <= n; i++) {

count = (--count + m) % ls.size();

System.out.print(ls.remove(count) + "  ");

}

}

public static void main(String[] args) {

new JosephRing().cac(7, 5);

}

}