## CCC '20 J4 - Cyclic Shifts (Hard)

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Points: 12 (partial)
Time limit: 0.4s
Java 0.6s
Python 0.7s
Memory limit: 512M

Author:
Problem type

This is an extension of ccc20j4. In this version constraints are higher. You can make hacks only if all versions of the problem are solved. Hacks are no longer being accepted.

Thuc likes finding cyclic shifts of strings. A cyclic shift of a string is obtained by moving characters from the beginning of the string to the end of the string. We also consider a string to be a cyclic shift of itself. For example, the cyclic shifts of ABCDE are:

ABCDE, BCDEA, CDEAB, DEABC, and EABCD.

Given some text, , and a string, , determine if contains a cyclic shift of .

#### Input Specification

The input will consist of exactly two lines containing only uppercase letters. The first line will be the text , and the second line will be the string .

##### Subtask 1 [90%]

Each line will contain at most characters.

##### Subtask 2 [10%]

Each line will contain at most characters.

Tip: the intended solution runs well within the time limit without constant optimization.

#### Output Specification

Output yes if the text, , contains a cyclic shift of the string, . Otherwise, output no.

#### Sample Input 1

ABCCDEABAA
ABCDE

#### Output for Sample Input 1

yes

#### Explanation of Output for Sample Input 1

CDEAB is a cyclic shift of ABCDE and is contained in the text ABC CDEAB AA.

#### Sample Input 2

ABCDDEBCAB
ABA

#### Output for Sample Input 2

no

#### Explanation of Output for Sample Input 2

The cyclic shifts of ABA are ABA, BAA, and AAB. None of these shifts are contained in the text ABCDDEBCAB.

## Comments

• commented on Jan. 30, 2022, 8:44 a.m. edit 4

Can this be solved using Python within the time limits? No accepted solutions for python or pypy exist.

 I see that there is an explicit time limit for python which suggests it ought to be solvable.

I'm stuck on 90%. Getting TLE on 2nd problem in part 3.

• commented on Jan. 29, 2022, 7:17 a.m.

A mystery to solve: why can't I exit() in python? I get NameError if I exit() rather than use logic to control program flow.

• commented on Jan. 29, 2022, 7:55 a.m.
• commented on Jan. 30, 2022, 8:45 a.m.

That would explain it :)

• commented on Jan. 30, 2022, 10:04 a.m.

you can still use sys.exit(0) however