我刚刚开始学习Python（昨天），我想知道如何更有效地制作我的第一个程序之一。
基本上，我的问题是我如何制作一个需要直接输入的程序，但是没有使用if else语句检查每种可能性。我的程序非常简单，只需要设置用户名和密码并重新输入，但我必须手动设置所有可能性。例如，如果您输入用户名并输入错误，则可以重置该用户名。谢谢您的帮助！
这是我的代码：
def main():
tries = 2
username = raw_input("Please enter a Username ")
confirmation = raw_input("Is your Username: " + username + "? ")
if(confirmation == "yes") or (confirmation == "Yes"):
password = raw_input("Please enter a Password for " + username + " ")
passconfirm = raw_input("Is your Password " + password + "? ")
if(passconfirm == "yes") or (passconfirm == "Yes"):
#username and password
enteruser = raw_input("Please enter your Username: ")
if(enteruser == username):
enterpass = raw_input("Please enter your Password for " + username + " ")
if(enterpass == password):
print("Welcome " + username)
else:
while(tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username + " ")
if (enterpass == password):
print("Welcome " + username)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while(enteruser != username):
enteruser = raw_input("Username not recognized, please retry ")
enterpass = raw_input("Please enter your Password for " + username + " ")
if (enterpass == password):
print("Welcome " + username)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username + " ")
if (enterpass == password):
print("Welcome " + username)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while(passconfirm != "yes") and (passconfirm != "Yes"):
#username and password2
password2 = raw_input("Please re-enter a Password for " + username + " ")
passconfirm = raw_input("Is your Password " + password2 + "? ")
enteruser = raw_input("Please enter your Username: ")
if (enteruser == username):
enterpass = raw_input("Please enter your Password for " + username + " ")
if (enterpass == password2):
print("Welcome " + username)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username + " ")
if (enterpass == password2):
print("Welcome " + username)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while (enteruser != username):
enteruser = raw_input("Username not recognized, please retry ")
enterpass = raw_input("Please enter your Password for " + username + " ")
if (enterpass == password2):
print("Welcome " + username)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username + " ")
if (enterpass == password2):
print("Welcome " + username)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while(confirmation != "yes") and (confirmation != "Yes"):
username2 = raw_input("Please re-enter your Username ")
confirmation = raw_input("Is your Username: " + username2 + "? ")
password = raw_input("Please enter a Password for " + username2 + " ")
passconfirm = raw_input("Is your Password " + password + "? ")
if (passconfirm == "yes") or (passconfirm == "Yes"):
#username2 password
enteruser = raw_input("Please enter your Username: ")
if (enteruser == username2):
enterpass = raw_input("Please enter your Password for " + username2 + " ")
if (enterpass == password):
print("Welcome " + username2)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username2 + " ")
if (enterpass == password):
print("Welcome " + username2)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while (enteruser != username2):
enteruser = raw_input("Username not recognized, please retry ")
enterpass = raw_input("Please enter your Password for " + username2 + " ")
if (enterpass == password):
print("Welcome " + username2)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username2 + " ")
if (enterpass == password):
print("Welcome " + username2)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while (passconfirm != "yes") and (passconfirm != "Yes"):
#username2 password2
password2 = raw_input("Please re-enter a Password for " + username2 + " ")
passconfirm = raw_input("Is your Password " + password2 + "? ")
enteruser = raw_input("Please enter your Username: ")
if (enteruser == username2):
enterpass = raw_input("Please enter your Password for " + username2 + " ")
if (enterpass == password2):
print("Welcome " + username2)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username2 + " ")
if (enterpass == password2):
print("Welcome " + username2)
exit()
else:
tries = tries - 1
print("Password incorrect")
else:
while (enteruser != username2):
enteruser = raw_input("Username not recognized, please retry ")
enterpass = raw_input("Please enter your Password for " + username2 + " ")
if (enterpass == password2):
print("Welcome " + username2)
else:
while (tries > 0):
enterpass = raw_input("Incorrect Password, Please re-enter your Password for " + username2 + " ")
if (enterpass == password2):
print("Welcome " + username2)
exit()
else:
tries = tries - 1
print("Password incorrect")
main（）的