判断:if/else
score=int(input('请输入一个分数:')) if 80>score>=60: print('C') elif 90>score>=80: print('B') elif 60>score>=0: print('D') elif 100>=score>=90: print('A') else: print('输入错误!')
条件:while(循环体)
bingo='我爱你' answer=input('你老婆最想听的一句话:') while True: if answer==bingo: break answer==input('抱歉,错啦!请重新输入:') print('哎呦,你真了解你老婆啊~~~')
for循环:目标 in 表达式;range([strat,]stop[,step=1]):
favorite="I love you!"
for o in favorite: print(o,end=' ') I l o v e y o u !
for i in range(1,10,2): print(i) 1 3 5 7 9
条件表达式:三元操作符 small=x if x<y else y
断言:assert(测试:检查程序中某个条件为真才能正常运行)
break:终止当前循环,跳出循环体
while True: while True: break print(1) print(2) break print(3)
continue:终止本轮循环并开始下一轮循环
count = 3 password = 'FishC.com' while count: passwd = input('请输入密码:') if passwd == password: print('密码正确,进入程序......') break elif '*' in passwd: print('密码中不能含有"*"号!您还有', count, '次机会!', end=' ') continue else: print('密码输入错误!您还有', count-1, '次机会!', end=' ') count -= 1