Master Python: List Files, Print Patterns, and Build Simple Utilities

1. List Files in Current and Subdirectories

Use Python's os.walk to enumerate all files under a given directory and print their absolute paths.

#!/usr/bin/env python
import os
for root, dirs, files in os.walk('/tmp'):
    for name in files:
        print(os.path.join(root, name))

The os.walk function returns a tuple (dirpath, dirnames, filenames) for each directory.

2. Print a Text Triangle

A simple script that asks for a number and prints a left‑aligned triangle of asterisks.

#!/usr/bin/env python
input = int(raw_input('input number:'))
for i in range(input):
    for j in range(i):
        print '*',
    print '
'

3. Number Guessing Game

The program generates a random digit, prompts the user to guess, and prints a triangle on success; otherwise it asks to try again.

#!/usr/bin/env python
import random
while True:
    input = int(raw_input('input number:'))
    random_num = random.randint(1, 10)
    print input, random_num
    if input == random_num:
        for i in range(input):
            for j in range(i):
                print '*',
            print '
'
    else:
        print 'please input number again'

4. Generate Disk Usage Log File

This script captures the output of df -h, formats it, and writes it to a log file named with the current date.

#!/usr/bin/env python
#!coding=utf-8
import time
import os
new_time = time.strftime('%Y-%m-%d')
disk_status = os.popen('df -h').readlines()
str1 = ''.join(disk_status)
f = file(new_time + '.log', 'w')
f.write('%s' % str1)
f.flush()
f.close()

5. Count IP Accesses from a Log File

Read a log file, extract IP addresses, and print how many times each IP appears.

#!/usr/bin/env python
#!coding=utf-8
ip_list = []
f = file('/tmp/1.log')
lines = f.readlines()
f.close()
for line in lines:
    ip = line.split()[0]
    ip_list.append(ip)
unique_ips = set(ip_list)
for ip in unique_ips:
    count = ip_list.count(ip)
    print '%s : %s' % (ip, count)