1.
注释 加#单行注释，''' '''多行注释
关键词 import keyword - keyword.kwlist
格式化输出 %d数字占位符 %s字符串占位符
例1:
age = 18
print(f"我的年纪是{age}岁")
print(f"我的年纪是:%d岁" % age)
print("我的名字是：%s,我的国籍是：%s" % ("小王", "中国"))
print("www", "baidu", "com", sep=".") # sep表示分割
print("hello", end="")
print("world", end="\t") # 后面加一个tab即空格键
print("python", end="\n") # 换行
print("end")
2.判断数值类型
a = "abc"
print(type(a)) # 输出a的类型
import random # 引入随机数库
x = random.randint(0, 2) # 随机生成[0,2],包含0,1,2
print(x)
3.for循环
for i in range(12):
print(i)
name = "chengdu"
for i in name:
print(i, end="\t")
a= ["aa", "bb", "cc", "dd"]
for i in range(len(a)):
print(i, a[i])
4. while循环
i = 0
while i < 5:
print("当前是第%d次循环"%(i+1))
print("i=%d"%i)
i += 1
例：1-100求和
n = 100
sum = 0
counter = 1
while counter <= n:
sum= sum + counter
counter += 1
print("1到%d的和为：%d"%(n, sum))
*break与continue
i = 0
while i <= 10:
i = i +1
print("-"*5)
if i == 5:
break #结束整个循环
print(i)
i = 0
while i <= 10:
i = i +1
print("-"*5)
if i == 5:
continue #结束本次循环
print(i)
