Problem Statement | |||||||||||||
Square cypher is very simple and easy to decrypt. It encrypts a message s=s0s1...sn-1 in the following way: all characters situated on square positions (0, 1, 4, 9, 16...) are moved to the front of the message. The relative order of the moved characters remains the same. For example, the message "thisisacontest" will be encrypted as "thinissacotest". You are given a String cryptogram. Decrypt it and return the result. | |||||||||||||
Definition | |||||||||||||
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Constraints | |||||||||||||
- | cryptogram will contain between 1 and 50 characters, inclusive. | ||||||||||||
- | cryptogram will contain only lowercase letters ('a'..'z'). | ||||||||||||
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