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:
Aaeria
Problem type

This is an extension of ccc20j4. In this version, the constraints are higher.

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, T, and a string, S, determine if T contains a cyclic shift of S.

Input Specification

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

Subtask 1 [90%]

Each line will contain at most 200\,000 characters.

Subtask 2 [10%]

Each line will contain at most 10^7 characters.

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

Output Specification

Output yes if the text, T, contains a cyclic shift of the string, S. 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


  • 0
    juniper3041  commented on Jan. 30, 2022, 1:44 p.m. ← edit 4

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

    [Edit] 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.


  • 1
    juniper3041  commented on Jan. 29, 2022, 12:17 p.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.