"""
Program: Print numbers with a thousand separator using spaces.
Architecture notes:
-------------------
- Python's format specification mini-language supports grouping with commas.
- To use spaces instead of commas, we format with commas first, then replace.
- This approach is simple, efficient, and avoids locale dependencies.
- The formatting function is isolated for clarity and reuse.
Performance notes:
------------------
- Formatting is O(n) in the length of the number string.
- Memory usage is minimal; only small strings are created.
- No external libraries; uses Python's built-in formatting.
Pitfalls:
---------
- Locale-based formatting may vary across systems; this solution avoids that.
- Very large integers are safe because Python integers have arbitrary precision.
- Negative numbers must preserve the minus sign.
Security notes:
---------------
- No external input parsing; safe for demonstration.
- Avoid formatting untrusted data if used in logging sensitive information.
Tests:
------
- Multiple test cases in main() demonstrate:
* Positive numbers
* Negative numbers
* Zero
* Very large integers
* Edge case: extremely large integer
"""
def format_with_space_separator(n):
"""
Format an integer using spaces as thousand separators.
Steps:
- Use Python's built-in format specifier: format(n, ",")
- Replace commas with spaces.
"""
try:
return format(n, ",").replace(",", " ")
except Exception as exc:
# Fallback: convert to string without formatting
return f"(unformatted due to error: {exc})"
def main():
test_values = [
0,
42,
1234,
987654321,
-1234567,
10**30, # very large integer
]
print("Running test cases:\n")
for value in test_values:
formatted = format_with_space_separator(value)
print(f"Original: {value}")
print(f"Formatted: {formatted}\n")
if __name__ == "__main__":
main()
'''
run:
Running test cases:
Original: 0
Formatted: 0
Original: 42
Formatted: 42
Original: 1234
Formatted: 1 234
Original: 987654321
Formatted: 987 654 321
Original: -1234567
Formatted: -1 234 567
Original: 1000000000000000000000000000000
Formatted: 1 000 000 000 000 000 000 000 000 000 000
'''
