# Python Interview with a Microsoft engineer

#### Watch someone solve the currency conversion problem in an interview with a Microsoft engineer and see the feedback their interviewer left them. Explore this problem and others in our library of interview replays.

## Interview Summary

### Problem type

Currency Conversion

### Interview question

Given the above parameters, find the conversion rate that maps to the 'from' currency to the 'to' currency for every single query

### Interview Feedback

#### Feedback about Crimson Almond (the interviewee)

Advance this person to the next round?  **Yes**  
How were their technical skills?  **4/4**  
How was their problem solving ability?  **4/4**  
What about their communication ability?  **4/4**

> 🎉 Summary:
> Interviewee is very solid, if I interviewed him at Microsoft for an Intern position, whether it's a technical phone screen or a virtual onsite, It would be a pass for me.

### Interview Transcript

Crimson Almond: Hello! Can you hear me?  
Winter Pumpkin: Yeah I can hear you.  
Crimson Almond: Just is my voice audible.  
Winter Pumpkin: Yes, I can hear your voice pretty well.  
Crimson Almond: Alright all good. Yo how's your day been?  
Winter Pumpkin: Yeah, I'm doing pretty good. How was yours?  
Crimson Almond: Fantastic. Thanks for asking again.

Crimson Almond: Yeah, thank you. So right now, I am a third. I'm a college student. I am a third year, computer science major. I go to a public school in California. And tomorrow, actually, I have an intern interview coming up for amazon.

Winter Pumpkin: Cool. So yeah, my name is Derek and I work in the operation analytics team. We do a lot of dashboarding.

Crimson Almond: Yeah, so if you don't mind, just kind of let me know like, you know, what you're looking for currently? How can I support you?

Winter Pumpkin: If you could go to Line 80.

Crimson Almond: Alright. Yes. So...

### Coding Task

```python
from typing import List, Dict

def get_conversions(rates: List[List[str]], queries: List[List[str]]) -> List[float]:
    adjacency_list = {}
    for rate in rates:
        from_currency, to_currency, conversion_rate = rate[0], rate[1], float(rate[2])
        adjacency_list.setdefault(from_currency, []).append((to_currency, conversion_rate))
        adjacency_list.setdefault(to_currency, []).append((from_currency, 1/conversion_rate))
    results = []
    for query in queries:
        src, dst = query[0], query[1]
        if src not in adjacency_list or dst not in adjacency_list:
            results.append(-1.0)
            continue
        # Perform BFS or DFS here to find the conversion
        found = False
        # Code for BFS or DFS goes here
        results.append(conversion_result if found else -1.0)
    return results
```

### Suggestions for Improvement

1. **Clarify Input**: Clarifying on the input and size to avoid friction during the interview.
2. **Efficiency**: Mention the potential impact of floating point division on accuracy over long paths.
3. **Use of Data Structures**: Consider using `deque` for BFS to improve efficiency.
4. **Exception Handling**: Adding error handling for unexpected inputs can enhance code robustness. 
5. **Refactor Code**: Ensure that the code is neat and well-structured to showcase clarity in logic.