Java 中 Hofstadter 的 G 序列递归

问题描述

我正在使用递归在 Java 中构建 Hofstadter 的 G 序列，但它没有按预期工作。

Hofstadter G 序列定义如下：

G(0)=0
G(n)= n-G(G(n-1)),n>0

这个数列的前几项是 0,1,2,3,4,5,6,7,8,9,10,11,12,...

我编写的以下方法目前不起作用：

  public static int G(int n) { 
    int i=0;
    int result = 0;

    if(n==0) return 0;

    for (i = 1; i <= n; i++) {
       result= i - G(G(i - 1));
       System.out.println(result);
    }

    return result;
  }

解决方法

可以直接根据定义实现递归方法：

df <- 
structure(list(country = c("USA","USA","Bolivia","Portugal","Portugal"),metric = c("MetricA","MetricA","MetricB","MetricB"),value = c("12","10","8","23","4","14","12","1","23"),minimum_age = c("0","15","0","3","30","19"),maximum_age = c("14","199","2","29","18","50")),class = "data.frame",row.names = c(NA,-10L))

为了优化这一点，您可以考虑使用记忆功能。