实验4

with open('data1_1.txt', 'r', encoding = 'utf-8') as f:
    n = 0
    for line in f:
        if line.strip('\n') == '':
            continue
        n += 1

print(f'共{n}行')

　　

with open('data2.txt', 'r', encoding = 'utf-8') as f:
    data = f.read().split('\n')

unique_line = []
for line in data:
    if data.count(line) == 1:
        unique_line.append(line)

print(f'共{ len(unique_line) }独特行')
for i in unique_line:
    print(i)

　　

ls = [ ['城市', '大致人口'],
       ['南京', '850万'],
       ['纽约', '2300万'],
       ['东京', '3800万'],
       ['巴黎', '1000万'] ]

with open('data3.csv', 'w', encoding = 'utf-8') as f:
    for line in ls:
        data = ','.join(line) + '\n'
        f.write(data)

with open('data3.csv', 'r', encoding = 'utf-8') as f:
    data = f.read()

print(data.replace(',', '\t'), end = '')

　　

import csv
ls = [ ['城市', '大致人口'],
       ['南京', '850万'],
       ['纽约', '2300万'],
       ['东京', '3800万'],
       ['巴黎', '1000万'] ]

with open('data4.csv', 'w', encoding = 'utf-8', newline = '') as f:
    writer = csv.writer(f)
    writer.writerows(ls)
with open('data4.csv', 'r', encoding = 'utf-8') as f:
    reader = csv.reader(f)
    for line in reader:
        print('\t'.join(line))