实验4

with open('data6_1.txt', 'r', encoding='utf-8') as f:
    d = f.read().split('\n')
    
    d1 = [str(i).split('\t') for i in d]

d1.sort(key=lambda x: x[2], reverse=True)
with open('data6_2.txt', 'w+',encoding='utf-8')as f:
    for line in d1:
         for i in line:
             f.write(i + '\t')
             print(i + '\t', end='')
             f.write('\n')
             print()

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

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('data1_2.txt', 'r', encoding = 'utf-8') as f:
    n = 0
    for line in f:
        if line.strip() == '':
            continue
        n += 1
print(f'共{n}行')

with open('data1_2.txt', 'r', encoding = 'utf-8') as f:
    n = 0
    for line in f:
        if line.isspace():
            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)

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))