Python字符串、循环及练习

s1 = "A better man"

# 无参以空格分割，有参以参数分割
list1 = s1.split()

# ['A', 'better', 'man']
print(list1)

c = 0

for i in list1:
    if len(i) > 0:
        c += 1

print(c)  # 结果：3

# 按照 \r \r\n \n 分隔

s1 = """Good man!
Good man!
"""

# 参数默认为False，True会保留换行符

# ['Good man!', 'Good man!']
print(s1.splitlines())

# ['Good man!\n', 'Good man!\n']
print(s1.splitlines(True))

# 从第一个字符开始比较ASCII码值大小

# 注:比较对应位置字符ASCII码值的大小
# 相同依次往后比较，不是按长度比较

print("b" > "az")    # 结果：True

print("msi" > "ms")  # 结果：True

list1 = ['Good', 'man']

# 通过空格将列表连接成字符串
s1 = ' '.join(list1)

print(s1)  # Good man      

s1 = "AA AA"

s2 = s1.replace("AA", "BB", 1)
# BB AA
print(s2)

s3 = s1.replace("AA", "BB")
# BB BB
print(s3)

# 注意：s1仍未被改变
# AA AA
print(s1)

s1 = "AA"

# 映射表为 A-C
s2 = s1.translate(str.maketrans("AA", "BC"))

print(s2)  # CC

s1 = "Mark"

# 编码
data1 = s1.encode("utf-8", "ignore")

# 解码要与编码保持一致
s2 = data1.decode("gbk", "ignore") 

# 无ignore时 鎴戞槸Mark 出现乱码
print(s2)                                 

# 死循环，别运行
while 1:
    print("爱你一万年")


# while else 语句

a = 1

while a <= 3:
    print("I love you")
    a += 1
else:
    print("Go away")

print("We will be better")                            

# for语句

for i in [1, 2, 3, 4, 5]:
    print(i)                       

# 生成一个0-9的列表
l = range(10)

# range(0, 10)
print(l)

# 遍历列表
for i in l:
    print(i)

# 从2开始，每次增加2，遍历到8  
for i in range(2, 10, 2):
    print(i)