第四章课后习题

4.1

GuessANum.py

target=425
guess=0
count=0
while guess!=target:
guess=eval(input('请输入一个猜测的整数(1-1000)😂)
count += 1
if guess>target:
print('猜大了')
elif guess<target:
print('猜小了')
else:
print("猜对了,总共猜了{}次".format(count))

4.2
s = input("请输入一行字符：")
letters = 0
digits = 0
spaces = 0
others = 0
for char in s:
if char.isalpha():
letters +=1
elif char.isdigit():
digits += 1
elif char.isspace():
spaces += 1
else:
others += 1
print(f"英文字符：{letters}个")
print(f"数字：{digits}个")
print(f"空格：{spaces}个")
print(f"其他字符：{others}个")

4.3
a = int(input("😊)
b = int(input("😊)
def gcd(a,b):
while b != 0:
a,b = b,a%b
return a
def lcm(a,b):
return abs(a*b)//gcd(a,b)
print(f"最大公约数：{gcd(a,b)}")
print(f"最小公倍数：{lcm(a,b)}")

4.4
import random
target=random.randint(0,1000)
guess=0
count=0
while guess!=target:
guess=eval(input('请输入一个猜测的整数(1-1000)😂)
count += 1
if guess>target:
print('猜大了')
elif guess<target:
print('猜小了')
else:
print("猜对了,总共猜了{}次".format(count))

4.5
import random
target=random.randint(0,1000)
count = 0
print("请输入一个0~1000的整数")
while True:
while True:
try:
guess = int(input("请输入你的猜测："))
break
except ValueError:
print("输入内容必须为整数！请重新输入：")

count += 1
if guess>target:
    print('猜大了')
elif guess<target:
    print('猜小了')
else:
    print("猜对了,总共猜了{}次".format(count))  
    break

4.6
try:
year=int(input("请输入一个年份："))
if (year%4000) or (year%40 and year%100 !=0):
print(f"{year}年是闰年")
else:
print(f"{year}年不是闰年")
except ValueError:
print("输入错误")

4.7
while True:
user_input=input("请输入一个十进制的全数字整数：")
if user_input.isdigit()：
print("输入正确")
break
else:
print("输入无效")

4.8
import re
while True:
user_input = input("请输入一个浮点数（必须包含小数点）：")
if re.fullmatch(r'^[1]?\d+.\d+$', user_input):
num = float(user_input)
print(f"输入正确！您输入的浮点数是：{num}")
break
else:
print("输入无效！必须为带小数点的浮点数，且不能使用科学计数法。")

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1. +- ↩︎