DCP-41: Innovative Birthday Gift! Back to All Problems

Easy Math > Number Theory

Tom and Jerry are not just any normal boys like others in their class. They are the best programmers in their class. Today is their birthday. So Mike decided to gift something on their birthday. As they happen to be well known programmers, Mike thought of something innovative. He sent an encrypted message to them in which the instruction for finding the gift has been written. If they desire to get their birthday gift, they have to decode the message given in the message and follow the instructions given in the message. The nature of encryption is described below: Prime numbers the positive integers which are only divisible by 1 and surely, number itself. The first of this kind is 2, then comes 3, 5, 7….. and so on. The ith letter of the original message is represented by a number ai. Let *m* is the nearest prime number less than or equal to *ai*. Now if *m* is the *r* th prime (like 2 is the 1st prime, 3 is the 2nd prime), the decoded letter would be ((*r* modulo 26)+1) th lowercase letter in the alphabet. A ‘0’ represents a space (' ') and '-1' represents a period ('.'). For example, let the encoded message contains three numbers like 12 17 -1. The nearest prime less than or equal to 12 is 11. 11 is the 5th prime. (5 modulo 26)+1=6. The 6th letter is ‘f’. Similarly 17 is the 7th prime and (7 modulo 26)+1=8. So the letter is ‘h’. Therefore, the decoded message for the sequence ‘12 17 -1’ represents “fh.”. You need to decode the message and help them get their birthday gift. Input: ------ The first line of input contains *t*, the number of test cases (1<=*t*<=10). For each of next *t* cases, there is a number *n* (1<=*n*<=100) which is followed by *n* space separated integers ai (-1<=*ai*<10000). Output: ------- Print the decrypted messages in separate lines. Sample Input ------------ 2 18 3324 0 6791 7741 3798 6883 8161 0 1873 3254 6302 373 7688 0 7151 7229 6842 -1 13 8707 7452 19 1224 0 3182 9161 0 8804 4391 5867 5280 -1 Sample Output ------------- a quick brown fox. this is easy.

Problem Limits

 Language Time Limit (seconds) C 1.00 C++ 1.00 C++14 1.00 C# 1.00 Go 1.00 Java 1.00 JavaScript 1.00 Objective-C 1.00 Perl 1.00 PHP 1.00 Python 1.00 Python3 1.00 Ruby 1.00 VB.Net 1.00

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Ranking

# User Language Timing
01 MAHRahat Cpp14 0.00s
02 pulak_ict_mbstu Cpp 0.00s
03 mahbub07 Cpp14 0.00s
04 feodorv C 0.00s
05 sadia2427 Cpp14 0.00s
06 Not_Found0001 Cpp 0.00s
07 mir003 Cpp14 0.01s
08 Morass Cpp14 0.01s
09 Dragon_162 Cpp14 0.01s
10 nazmul_bzs Cpp14 0.01s
11 anik_JU Cpp14 0.01s
12 Ansarul_14 Cpp14 0.01s
13 afzalul Cpp 0.01s
14 Dinar Cpp14 0.01s
15 Logic_Hunter Cpp 0.01s
16 emrul Cpp14 0.01s
17 mhsjaber CSharp 0.03s
18 anis Cpp14 0.07s
19 Najat Cpp14 0.07s
20 Md_Abid Cpp14 0.09s
21 RandyWaterhouse Python3 0.16s
22 zifan Cpp14 0.22s
23 khayrul Cpp14 0.25s
24 Gias_uddin Cpp14 0.26s
25 abinash Cpp14 0.27s
26 mtmohim Cpp14 0.28s
27 Anik7703 Cpp14 0.31s
28 talha629 Cpp14 0.32s
29 mamun4122 Cpp14 0.34s
30 bhadra Cpp14 0.40s
31 kanon2 Cpp14 0.40s
32 shaheen_bd Cpp14 0.40s
33 Unseen Cpp14 0.40s
34 howcum Cpp14 0.40s
35 sajal_khan Cpp14 0.40s
36 Digonta Cpp14 0.40s
37 BinaryFlip Cpp14 0.40s
38 jahid_ict Cpp14 0.40s
39 moshiur_cse15 Cpp14 0.40s
40 Unpredictable Cpp14 0.41s
41 haasib Cpp14 0.41s
42 anowar1112 Cpp14 0.41s
43 INUA Cpp14 0.41s
44 khatribiru Cpp14 0.41s
45 sahedsohel Cpp14 0.41s
46 subhashis_cse Cpp14 0.42s
47 Fahim_Ahmed Cpp14 0.42s
48 Roki_Moulik_12_EWU Cpp14 0.43s
49 Sarwar_sojol Cpp14 0.43s
50 astrolion7 Cpp14 0.43s
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