1.求1-100的所有数的和
sum = 0 for i in range(101): sum = sum + i print(sum)
2.1-100内的基数
m = 0 while m < 101: i = m%2 if i == 1: print(m) m += 1
3.1 - 100以内的偶数
m = 0 while m < 101: i = m%2 if i == 0: print(m) m += 1
4. 求1-2+3-4+5 ... 99的所有数的和
n = 0 m = 0 while [1]: if 0 == n % 2: m = m - n else: m = m + n if n == 100: break n += 1 print(m)
5. 用户登录(三次错误机会)
import sys user_list = [ {'username': 'alex', 'password': '123'}, {'username': 'eric', 'password': '123'}, {'username': 'tony', 'password': '123'}, {'username': 'oldboy', 'password': '123'}, ] flag = False count = 0 while True: user = input("请输入用户名:") pwd = input("请输入密码:") for item in user_list: if item['username'] == user and item['password'] == pwd: flag = True else: pass if flag: print("登录成功") exit() else: print("登录失败,请重新登录") count += 1 if count == 3: print('您输入的用户密码错误超过3次,已经退出') exit()