Problem p02910 - Generation 2

Orig Description

Score: 200 points
Problem Statement
Takahashi will do a tap dance. The dance is described by a string S where each character is L, R, U, or D. These characters indicate the positions on which Takahashi should step. He will follow these instructions one by one in order, starting with the first character.
S is said to be easily playable if and only if it satisfies both of the following conditions:
Every character in an odd position (1-st, 3-rd, 5-th, \ldots) is R, U, or D.
Every character in an even position (2-nd, 4-th, 6-th, \ldots) is L, U, or D.
Your task is to print Yes if S is easily playable, and No otherwise.
Constraints
S is a string of length between 1 and 100 (inclusive).
Each character of S is L, R, U, or D.
Input
Input is given from Standard Input in the following format:
S
Output
Print Yes if S is easily playable, and No otherwise.
Sample Input 1RUDLUDR
Sample Output 1Yes
Every character in an odd position (1-st, 3-rd, 5-th, 7-th) is R, U, or D.
Every character in an even position (2-nd, 4-th, 6-th) is L, U, or D.
Thus, S is easily playable.
Sample Input 2DULL
Sample Output 2No
The 3-rd character is not R, U, nor D, so S is not easily playable.
Sample Input 3UUUUUUUUUUUUUUU
Sample Output 3Yes
Sample Input 4ULURU
Sample Output 4No
Sample Input 5RDULULDURURLRDULRLR
Sample Output 5Yes

Extracted Specification

An integer N (1 ≤ N ≤ 100), representing the length of the sequence.
A string S of length N, where each character is 'L', 'R', 'U', or 'D'.

### Example Input:

```
8
RUDLUDR
```

### Function Signature:
Write a function f(N, S) that takes in the input.
```python
def f(N: int, S: str):
    '''
    N: an integer
    S: a string
    '''
```

Test Case Generator

Sure, I can write a test case generator for the given problem statement. Below is the Python code to generate random test cases for the problem "Takahashi's Tap Dance":

```python
import random

def tcgen():
    # Length of the string S, between 1 and 100 inclusive
    length = random.randint(1, 100)
    
    # Characters in S are L, R, U, or D
    characters = ['L', 'R', 'U', 'D']
    
    # Generate a random string of the specified length using the characters
    S = ''.join(random.choice(characters) for _ in range(length))
    
    return S

# Example usage
if __name__ == "__main__":
    for _ in range(5):  # Generate 5 test cases
        print(tcgen())
```

### Explanation:
- The `tcgen` function generates a random test case for the problem.
- The length of the string \( S \) is randomly chosen between 1 and 100 inclusive.
- Each character in the string \( S \) is randomly chosen from the set {'L', 'R', 'U', 'D'}.
- The function returns the generated string \( S \).

### Sample Output:
Running the `tcgen` function multiple times might produce outputs like:
```
LURD
ULRUD
DDDUUU
LRLRLR
URDL
```

These outputs represent different possible dance instructions for Takahashi according to the constraints and format described in the problem statement.

Extract Arguments

def extract_arguments(fh):
    S = fh.readline().strip()
    return S