# SkyWT

Fighting 2019！

## Description

Ivan wants to make a necklace as a present to his beloved girl. A necklace is a cyclic sequence of beads of different colors. Ivan says that necklace is beautiful relative to the cut point between two adjacent beads, if the chain of beads remaining after this cut is a palindrome (reads the same forward and backward).

## Description

In mathematical terms, the sequence F_n of Fibonacci numbers is defined by the recurrence relation

F_1 = 1; F_2 = 1; F_n = F_{n - 1} + F_{n - 2} (n > 2)

DZY loves Fibonacci numbers very much. Today DZY gives you an array consisting of n integers: a_1, a_2, \dots, a_n. Moreover, there are m queries, each query has one of the two types:

## Description

• 孙某说：如果我不知道的话，张某肯定也不知道。
• 张某说：刚才我不知道，听孙某一说，我现在知道了。
• 孙某说：哦，那我也知道了。

## Description

You are given a list of strings over the alphabet A (for adenine), C (cytosine), G (guanine), and T (thymine), and your task is to find the shortest string (which is typically not listed) that contains all given strings as substrings. If there are several such strings of shortest length, find the smallest in alphabetical/lexicographical order.

Time Limit: 4 second(s)
Memory Limit: 32 MB

## HDU 3555 Bomb

The counter-terrorists found a time bomb in the dust. But this time the terrorists improve on the time bomb. The number sequence of the time bomb counts from 1 to N. If the current number sequence includes the sub-sequence "49", the power of the blast would add one point.
Now the counter-terrorist knows the number N. They want to know the final points of the power. Can you help them?

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