三个数比较大小：
num1=input(“num1:”)
num2=input(“num2:”)
num3=input(“num3:”)
if num1>num2:
max_num=num1
if max_num>num3:
print(“max num is”,max_num)
else:
print(“max num is”,num3)
else:
max_num=num2
if max_num>num3:
print(“max num is”,max_num)
else:
print(“max num is”,num3)
运行的结果：
猜对年龄为止：
age=60
flag=True
while flag:
user_input_age=int(input(“age is:”))
if user_input_age==age:
print(“yes”)
flag=False
elif user_input_age>age:
print(“is bigger”)
else:
print(“is smaller”)
print(“end”)
运行结果：
break与continue的区别：
num=1
while num<=10:
print(num)
num+=1
if num==5:
break
num=1
while num<=10:
num+=1
if num==5:
continue
print(num)
while语句的双重循环：
num1=0
while num1<=5:
print(num1,end=”_”)
num2=0
while num2<=7:
print(num2,end=”-“)
num2+=1
num1+=1
print()
