方法，该方法检查该方法是否已使用该输入执行

Question

public class CatalanNumbers {

    private int howManyVariaties;
    private int catalanNumber;
    private int catalanNumber;

    public int catalan(int a) {
       if (Method was never executed with that input) {
              howManyVariaties++;
       int catalanNumber = 0;
       for (int i= 0; i < n; i++) {
           catalanNumber += catalan(i) * catalan( n- 1 -i);
       return catalanNumber

总而言之，我只想检查最大堆栈深度是多少。

有人能帮我吗？

Answer 1

向您的类添加一个跟踪使用了哪些输入的集合，并在方法中检查该集合

public class CatalanNumbers {

    private int howManyVariaties;
    private int catalanNumber;
    private int catalanNumber;
    private Set<Integer> alreadyHandled = new HashSet<>();

    public int catalan(int a) {
        if (alreadyHandled.add(a)) {                  
            //rest of code
        }
    }
//...
}