开发笔记:基本数据类型(intboolstr)

s = "今天中吃胡萝卜"
print(s[3]) # 吃
print(s[2]) # 中
print(s[-2]) # 萝
print(s[-6]) # 天

s = "中间的,你们为什么不说话.难受"
print(s[3:7]) #,你们为
print(s[5:9])#们为什么
print(s[-3:-7])#切不到东西
print(s[-7:-3])#么不说话
print(s[:6]) #中间的,你们
print(s[6:])#为什么不说话.难受
print(s[:])#中间的,你们为什么不说话.难受

s = "abcdefghijklmn"
print(s[::2]) #acegikm
print(s[1:5:3]) #be
print(s[7:3]) #切不到什么
print(s[7:3:-1]) #hgfe
print(s[-1:-8:-2]) #nljh

s = "黄山落叶松叶落山黄"
s2 = s[::-1]
if s == s2:
print("是回文")
else:
print("不是回文")

s = "abcdefg"
s1= s.capitalize() #把首字母大写
print(s1)#Abcdefg

s = "alex sb dsb wusir bi1gsb"
s2 = s.title() #把所有的首字母都大写
print(s2)#Alex Sb Dsb Wusir Bi1Gsb

s = "alex sb dsb wusir bi1gsb"
s3 = s.upper() #所有字母都大写
print(s3)#ALEX SB DSB WUSIR BI1GSB

s = "Alex Is Not A Or B"
s5 = s.lower() #对欧洲的特殊字符识别不了
print(s5)#alex is not a or b
s6 = s.casefold() #支持特殊文字
print(s6)#alex is not a or b
s2 = "БB?"
s7 = s2.lower()
print(s7)#бb?
s8 = s2.casefold()
print(s8)#бbss

s = "WuSir 昨天出去 Love 女生 呵呵"
s2 = s.swapcase() #大写变小写,小写变大写
print(s2)#wUsIR 昨天出去 lOVE 女生 呵呵
s = "alex"

s = "alex"
s6 = s.center(10,"*")#文字居中左右填充
print(s6) #***alex***　

name = "alex"
age = 18
hobby = "wusir"
print(f"领导叫{name},今年{age}岁,喜欢{hobby}")
print("领导叫{},今年{}岁,喜欢{}".format(name,age,hobby))
print("领导叫{n},今年{a}岁,喜欢{h}".format(n=name,a = age,h = hobby))
print("领导叫{0},今年{2}岁,喜欢{1}".format(name,age,hobby))

s = "
alex hhh 123 "
s2 = s.strip()#去除字符串左右两边的空白字符
print(s2)
s = "bb aa bb cc dd bb"
s2 = s.strip("bb") #去除左右两边的bb
print(s2)

s = " good alex good wusir good 大虾 good 胡辣汤 "
s8 = s.replace("大虾","大鱼") #文字的替换
print(s8)
s9 = s.replace(" ","")
print(s9)
s10 = s.replace("good","sb",2)
print(s10)

name = input("请输入你的名字:").strip()
if name.startswith("钱"): #是否以它开头
print("过来")
elif name.endswith("多"):#是否以它结尾
print("过来")
else:
print("走开")

s = "alex is big sb"
print(s.count("i"))#统计个数

s = "红烧猪蹄子"
print(s.find("烧")) #1
print(s.find("123")) #-1
print(s.index("烧")) #1
print(s.index("123")) #报错ValueError: substring not found

s = "alexwusir"
print(s.isalpha()) #纯字母,不包含数字 True

s = "123456789"
print(s.isdigit()) #纯数字,不包含其他字符 True

s = "我是周润发,我喜欢你"
print(len(s)) #10
s = input("请输入一句话:")
i = 0
while i print(s[i]) #10
i += 1