微软2016校园招聘在线笔试第二场 题目1 : Lucky Substrings

时间限制:10000ms

单点时限:1000ms

内存限制:256MB

描述

A string s is LUCKY if and only if the number of different characters in s is a fibonacci number. Given a string consisting of only lower case letters, output all its lucky non-empty substrings in lexicographical order. Same substrings should be printed once.

输入

A string consisting no more than 100 lower case letters.

输出

Output the lucky substrings in lexicographical order, one per line. Same substrings should be printed once.

样例输入

aabcd

样例输出

a

aa

aab

aabc

ab

abc

b

bc

bcd

c

cd

d

import java.util.HashSet;

import java.util.Scanner;

import java.util.TreeSet;







public class Main {

    public static HashSet<Integer> fibsetHashSet;

    static{

        fibsetHashSet= new HashSet<Integer>();

        fibsetHashSet.add(0);

        fibsetHashSet.add(1);

        fibsetHashSet.add(2);

        fibsetHashSet.add(3);

        fibsetHashSet.add(5);

        fibsetHashSet.add(8);

        fibsetHashSet.add(13);

        fibsetHashSet.add(21);

        fibsetHashSet.add(34);

        fibsetHashSet.add(55);

        fibsetHashSet.add(89);

    }

    public static boolean isFib(String sub){

        

        

        int count[]=new int[26]; //全是零

        

        if(sub.length()==0)return false;

        

        for(int i=0; i<sub.length(); i++){

            char a=sub.charAt(i);

            count[a-'a']+=1;

        }

        int diff=0;

        for( int i=0; i<26; ++i){

            if(count[i]!=0)++diff;

        }

        

        for( int i=0; i<26; ++i){

            if(!fibsetHashSet.contains(diff))return false; //如果不符合

        }

        return true;

    }

    public static void main(String args[]){

        Scanner scanner=new Scanner(System.in);

        String string=scanner.next();

        //String string="aabcd";

        TreeSet<String> set = new TreeSet<String>();



        

        int len=string.length();

        for(int i=0; i<len; i++){

            for(int j=i+1; j<=len; j++){

                String subString=string.substring(i, j);

                if(isFib(subString)){

                    set.add(subString);

                }

            }

        }

        for(String key: set){

            System.out.println(key);

        }

        //System.out.println(set);

    }

}