Python基础--基本逻辑语法

1.if-elif-else

age = input("please input your age...")    #获取控制台输入值
age = int(age)   #将字符串转整数
#逻辑判断年龄
if age<0:
    print("are you kdding me?")
elif age>=0 and age<18:
    print("you are a child")
else:
    print("you are a adult")

 

2.for

#简单循环
langurages = ["C","C++", "JAVA", "Python"]
for l in langurages:
    print(l)

#break跳出循环和continue本次循环结束，进入下一次循环
sites = ["baidu", "google", "bing"]
for s in sites:
    if s == "baidu":
        print("百度")
        break
    else:
        continue

#range()用来生成数字序列
for i in range(2,10):   #range(2,10) 2<=i<10
    print(i)    

#range(start,end,step)用法
#start 开始值，end结束值，step步长值
for i in range(2,10,2):
    print(i)

3.while

i, sum = 1,0
while i<=100:
    sum = sum+i
    i += 1
print("1至100的和为：%d",sum)