|시간 제한||메모리 제한||제출||정답||맞은 사람||정답 비율|
|1 초||128 MB||7||7||7||100.000%|
Farmer John's N cows (conveniently numbered 1..N) are forming a line. The line begins with no cows and then, as time progresses, one by one, the cows join the line on the left or right side. Every once in a while, some number of cows on the left or right side of the line all leave the line to go graze in their favorite pasture.
FJ has trouble keeping track of all the cows in the line. Please help him.
The cows enter the line in numerical order 1..N, and once a cow leaves the line she never re-enters it. Your program will be given S (1 <= S <= 100,000) input specifications; each appears on a single line and is one of two types:
Input lines never request an operation that can not be performed.
After all the input lines have been processed, your program should print the cows in the line in order from left to right. The final line is guaranteed to be non-empty at the end of the input specifications.
10 A L A L A R A L D R 2 A R A R D L 1 A L A R
7 2 5 6 8
Input Resulting Cow Line A L 1 A L 2 1 A R 2 1 3 A L 4 2 1 3 D R 2 4 2 A R 4 2 5 A R 4 2 5 6 D L 1 2 5 6 A L 7 2 5 6 A R 7 2 5 6 8