for i in range loop learning record

foreword

Recently, I want to review the loop statement. I just didn’t understand the for loop statement before. Let’s review it this time.

code show as below:

"""

for i in range 的循环

"""
"""
for i in range(n):
    pass
    
else:
    pass
"""
for i in range(3):   #range取值从“0”开始，包头不包尾
    username = input("请输入用户名：")
    password = input("请输入密码：")

    if username == "admin"and password == "123":
        print("用户登录成功！")
        break
    else:
        if i == 2:          #这里else下加的if 语句是让第三次输入错误的时候不输出else下的print，
            continue       #下方不能用break，要用continue 这样才能继续运行到外围的 for ....else
        print("账户或密码输入错误！请重新输入！\n")

else:
    print("由于您多次输入错误账号已锁定！") 

 #出现else 的情况必须是for中的语句被打断才会运行，只对python 有效