```python
def seat_run(row: str, party: int) -> int:
    if party == 0:
        return -1

    start = 0
    while start < len(row) and party > 0:
        if row[start] == '.':
            party -= 1
        start += 1

    if party == 0:
        return start - 1
    else:
        return -1
```