|Time limit : 3 s||Memory limit : 32 mb|
|Submitted : 1180||Accepted : 502|
In the land of Hedonia the official language
is Hedonian. A Hedonian professor had noticed that many of her students still
did not master the syntax of Hedonian well. Tired of correcting the many
syntactical mistakes, she decided to challenge the students and asked them to
write a program that could check the syntactical correctness of any sentence
they wrote. Similar to the nature of Hedonians, the syntax of Hedonian is also
pleasantly simple. Here are the rules:
0. The only characters in the language are the characters p through z and N, C, D, E, and I.
1. Every character from p through z is a correct sentence.
2. If s is a correct sentence, then so is Ns.
3. If s and t are correct sentences, then so are Cst, Dst, Est, and Ist.
4. Rules 0. to 3. are the only rules to determine the syntactical correctness of a sentence.
You are asked to write a program that checks if sentences satisfy the syntax rules given in Rule 0. - Rule 4.
Cp Isz NIsz Cqpq
NO YES YES NO