某金融公司一个编程题

1,1,2,3,5,8,13,21......请设计一个程序，第n项的值？

public class MoneyTest {
    public static void main(String[] args) throws IOException {
        InputStream in = System.in;
        BufferedReader br = new BufferedReader(new InputStreamReader(in));
        System.out.println("请输入第几项：");
        String s = br.readLine();
        int res = method(Integer.valueOf(s));
        System.out.println(res);
    }

    private static int method(Integer n) {
        if(n == 1 || n == 2){
            return 1;
        }
        int i = 1, j = 1, m = 0;
        boolean b = true; //定义此b是为了 交替给i和j赋值
        while(n > 2){
            m = i + j;
            if(b){
                b = false;
                i = m;
            }else{
                b = true;
                j = m;
            }
            n --;
        }
        return m;
    }
}