Arithmetic Progression Subsequences (1) X57357


Statement
 

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Write a program that reads two integers n and r, both strictly greater than 1, followed by a sequence of integers, and finds out whether the sequence contains a consecutive subsequence of length at least n that forms an arithmetic progression with step r.

A consecutive subsequence of integers forms an arithmetic progression with step r if the difference between two consecutive numbers equals r. For instance, 4 5 6 7 is an arithmetic progression with r = 1, and 22 33 44 55 66 is an arithmetic progression with r = 11.

If the input sequence contains such a progression, the program must print a line with the first n elements in the progression. Otherwise, the program must indicate "No arithmetic progression found with step r and length at least n".

Input

The input consists of two integers n>1 and r>1, followed by a sequence of integers containing at least 2 elements.

Output

If a progression subsequence with reason r and length at least n exists, the output are the first n elements of the progression. Otherwise, the output is "No arithmetic progression found with step r and length at least n".

Public test cases

  • Input

    4 1
7 1 -2 6 9 10 11 12 15

    Output

    9 10 11 12

  • Input

    4 1
7 1 -2 5 6 7 8 9 12 15

    Output

    5 6 7 8

  • Input

    5 11
7 1 -2 
10 21
32
43 54 
88 3 -5 -6

    Output

    10 21 32 43 54

  • Input

    5 3
2 4 6 8 10 12 14 21

    Output

    No arithmetic progression found with step 3 and length at least 5

  • Input

    5 3
7 1  2 5 8 11
32 43 54 
88 3 -5 -6

    Output

    No arithmetic progression found with step 3 and length at least 5
    • Information
    Author
    ProAl
    Language
    English
    Official solutions
    Python
    User solutions
    Python