判断语句

if True/False:
   pass
else:
   pass

// 嵌套if else
if True/False:
   if True/False:
       pass
   else:
       pass
else:
   pass

//elif取代switch分支
a = int(input())
if a == 1:
   pass
elif a == 2:
   pass
elif a == 3:
   pass
else:
   pass

循环语句

1. while循环

   while True/False:
     pass
   else:
     pass
   

2. for in 循环

   for name in names:
      pass
   
   // 嵌套循环
   for i in names:
       for a in i:
           pass
   else:
       pass
   
    // 循环一段代码10次，可以用来取代java中for(int i=0;i<10;i++){}
   for x in range(0, 10):
       pass
   

3. 终止循环
   continue-->终止当次循环的此次循环
   break-->终止当次循环，跳出
4. if else在python中没有块级作用域一说，在if else中定义的变量在外面也可以直接访问