实验4

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)

 

 

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)


# 从data3.csv中读出数据，把逗号替换成\t, 分行打印输出到屏幕上
with open('data3.csv', 'r', encoding = 'utf-8') as f:
    data = f.read()

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

 

 

import csv  # 导入csv模块

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)  # 使用csv模块的writer类创建对象
    writer.writerows(ls)


# 从data4.csv中读出数据，把逗号替换成\t, 分行打印输出到屏幕上
with open('data4.csv', 'r', encoding = 'utf-8') as f:
    reader = csv.reader(f) # 使用csv模块的reader类创建对象
    for line in reader:
        print('\t'.join(line))

 

 

 

 

 

 

def main():
    pass

if __name__ == '__main__':
    main()
with open('data6_1.txt','r',encoding='utf-8') as f:
    with open('data6-2.txt ','w',encoding='utf-8') as m:
        a = f.readlines()
        list1 = []
        for line in a:
            b = line.strip('\n').split('\t')
            list1.append(b)
        c = lambda list1:list1[2]
        list1.sort(key = c,reverse = True)
        for i in list1:
            m.write(' '.join(i)+'\n')
            print(i)

 

 

 

 

import random
name_num = eval(input('请输入抽点人数:'))
m = set()
with open('data7.txt','r') as f:
    a = f.readlines()
    while len(m)<name_num:
        b = random.randint(0,len(a)-1)
        m.add(a[b])

import datetime
time = datetime.datetime.now()
x = time.strftime('%Y%m%d')
with open(x+'.txt','w') as n:
    for i in m:
        n.write(i)
        print(i)