Account
GitHubFeedback
Drafts and results saved on this device
Submit on CSES.fi
CSES Problemset/Introductory Problems

Grid Path Description

#1625
Ask AI

Open a hint-first prompt in a new AI chat. Grok may ask you to confirm before sending.

Open Claude Desktop

Time limit:1.00 s
Memory limit:512 MB
Unsolved
Download Tests (.zip)

There are 8841888418 paths in a 7×77 \times 7 grid from the upper-left square to the lower-left square. Each path corresponds to a 4848-character description consisting of characters D (down), U (up), L (left) and R (right).

For example, the path

corresponds to the description DRURRRRRDDDLUULDDDLDRRURDDLLLLLURULURRUULDLLDDDD.

You are given a description of a path which may also contain characters ? (any direction). Your task is to calculate the number of paths that match the description.

Input

The only input line has a 4848-character string of characters ?, D, U, L and R.

Output

Print one integer: the total number of paths.

Sample Test Cases (1)
Example 1ID: sample-1
Input
??????R??????U??????????????????????????LD????D?
Expected Output
201
Tools
1
2
3
4
5
6
7
8
9
10
11
12
Draft saved locally
|1 line, 0 chars
Test Bench
Download .zip
Input (stdin)
??????R??????U??????????????????????????LD????D?
Expected Output
201