#R297B. [ABC297B] chess960
[ABC297B] chess960
Score : points
Problem Statement
Takahashi is playing a game called Chess960. He has decided to write a code that determines if a random initial state satisfies the conditions of Chess960.
You are given a string of length eight. has exactly one
KandQ, and exactly twoR's,B's , andN's. Determine if satisfies all of the following conditions.
- Suppose that the -th and -th characters from the left of are
B; then, and have different parities. Kis between twoR's. More formally, suppose that the -th and -th characters from the left of areRand the -th isK; then .
Constraints
- is a string of length that contains exactly one
KandQ, and exactly twoR's,B's , andN's.
Input
The input is given from Standard Input in the following format:
Output
Print Yes if satisfies the conditions; print No otherwise.
RNBQKBNR
Yes
The -rd and -th characters are B, and and have different parities.
Also, K is between the two R's. Thus, the conditions are fulfilled.
KRRBBNNQ
No
K is not between the two R's.
BRKRBQNN
No