public class DENO {
    static int N = 4;

    public static void main(String[] args) {
        int i;
        int x1 = 1, x2 = 2;
        System.out.println();
        for (i = 1; i <= N; i++) {
            System.out.print(x1+" "+x2);
            if (i % 2 == 0)      //不加大括号 不成立则执行在下一行的语句  成立的话三条语句都会执行
            System.out.println();
            x1 = x1 + x2;
            x2 = x2 + x1;
        }
    }
}

// 1 2 3 5
// 8 13 21 34