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Python Time & Space Complexity

Getopt

getopt Module¶

The getopt module provides command-line argument parsing using the GNU getopt() style (superseded by argparse but still useful for simple cases).

Complexity Reference¶

Operation	Time	Space	Notes
`getopt.getopt()`	O(n)	O(n)	n = command-line args
Argument parsing	O(n)	O(n)	Parse and store

Parsing Command-Line Arguments¶

Simple Argument Parsing¶

import getopt
import sys

# Parse args - O(n) where n = number of args
shortopts = "hv:"  # h=help (no arg), v=verbose (requires arg)
longopts = ["help", "version="]

try:
    opts, args = getopt.getopt(sys.argv[1:], shortopts, longopts)
except getopt.GetoptError as err:
    print(err)
    sys.exit(2)

# Process options - O(n)
for opt, arg in opts:
    if opt in ("-h", "--help"):
        print("Help message")
    elif opt in ("-v", "--version"):
        print(f"Version: {arg}")