CF1861A.Prime Deletion

普及/提高-

通过率:0%

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题目描述

A prime number is a positive integer that has exactly two different positive divisors: 11 and the integer itself. For example, 22 , 33 , 1313 and 101101 are prime numbers; 11 , 44 , 66 and 4242 are not.

You are given a sequence of digits from 11 to 99 , in which every digit from 11 to 99 appears exactly once.

You are allowed to do the following operation several (maybe zero) times: choose any digit from the sequence and delete it. However, you cannot perform this operation if the sequence consists of only two digits.

Your goal is to obtain a sequence which represents a prime number. Note that you cannot reorder the digits in the sequence.

Print the resulting sequence, or report that it is impossible to perform the operations so that the resulting sequence is a prime number.

输入格式

The first line contains one integer tt ( 1t50001 \le t \le 5000 ) — the number of test cases.

Each test case consists of one line containing a string of 99 digits (without any characters between them). Each digit from 11 to 99 appears in this string exactly once.

输出格式

For each test case, print the answer on a separate line as follows:

  • if it is impossible to perform the described operations, print 1-1 ;
  • otherwise, print any sequence that represents a prime number, which can be obtained from the given string performing several (maybe zero) operations described in the statement. If there are multiple such sequences, you can print any one of them.

输入输出样例

  • 输入#1

    4
    123456789
    987654321
    243567918
    576318429

    输出#1

    167
    53
    3571
    57638429
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