Python语言程序设计基础（4）—— 程序的控制结构

PM2.5

pm = eval(input())
if pm>=75:
    print("空气存在污染")
else :
    print("空气没有污染")

print("空气{}污染".format("存在" if pm>=75 else "没有"))

健康

height,weight = eval(input())
bmi = weight/(height**2)
who = ""
if bmi < 18.5:
    who = "偏瘦"
elif bmi < 25:
    who = "正常"
elif bmi < 30:
    who = "偏胖"
else:
    who = "肥胖"
print(who)

异常处理

try:
    num = eval(input())
    print(num*2)
except "输入错误":
    print("输入错误了")
else:
    print("没有输入错误")
finally:
    print("程序完成")

for c in "TreeDream":
    print(c,end="")
else :
    print("
正常结束")

random

from random import *

print(random())
print(uniform(1,10))
print(uniform(1,20))
print(randrange(0,15,5))
print(choice(range(100)))
ls = list(range(10))
print(ls)
shuffle(ls)
print(ls)

seed(125)
print("{}.{}.{}".format(randint(1,10),randint(1,10),randint(1,10)))
print("{}.{}.{}".format(randint(1,10),randint(1,10),randint(1,10)))
seed(125)
print("{}.{}.{}".format(randint(1,10),randint(1,10),randint(1,10)))

pi

import random
import math
import time

DARTS = 1000
hits = 0
#time.clock()

for i in range(DARTS+1):
    x,y = random.random(),random.random()
    dist = math.sqrt(x**2+y**2)
    if dist <=1:
        hits+=1
print("{}".format(4*hits/DARTS))

习题部分

猜数字

import random

x = random.randint(0,100)
print(x)

cnt = 1
g = eval(input())
try:
    while x != g :
        cnt+=1
        print("{}".format("大" if g > x else "小"))
        g = eval(input())
    print("猜了{}次".format(cnt))
except "input error" :
    print("输入错误")

　gcd

def gcd(a,b):
    if b == 0:
        return a
    else :
        return gcd(b,a%b)

print(gcd(102,9))