Moving intervals for packing and covering

2 problems from Moving intervals for packing and covering (contest 103230), difficulty -. 0/2 solutions verified against sample I/O.

2 items

Moving intervals for packing and covering

Special | 2 problems | 0/2 verified | Difficulty - | 3m 8s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Torty and Shields				2m 26s
B	Blue Puppy and UFOs				42s

Practice › Codeforces Solutions › Moving intervals for packing and covering ›

CF 103230A - Torty and Shields

Let $n=s+t$ and let the ground positions be ${0,1,dots,n-1}$. A configuration is a word $x0x1cdots x{n-1}$ over ${0,1,ast}$ containing exactly $t$ asterisks. The set of all such configurations has size $2^sbinom{s+t}{t}$.

Practice › Codeforces Solutions › Moving intervals for packing and covering ›

CF 103230B - Blue Puppy and UFOs

The problem statement for “Codeforces 103230B - Blue Puppy and UFOs” is not included in your message, so I don’t have enough information to write a correct editorial.