前言
本文为牛客的在线编程的python入门题集的个人解析 链接:
本人主语言C/C++ 来这边刷一下python的入门语法题,这个题库很基础很入门真的就是纯考python语法
本文虽然是展示AC代码,但实际是为了记录python的各种基础语法,便于以后遗忘了可以查看
本文代码默认在python3环境
牛客的环境是版本:Python3.9,支持大部分的常用库。Numpy库与SciPy库默认不支持,请根据题目要求查看是否支持。
AC代码
01 输入输出
NP1 Hello World!
# python 中的字符串
# 用单引号或者双引都可以
# 结尾加不加;都可以
# 这两点和JavaScript很像
print("Hello World!")
NP2 多行输出
str1 = "Hello World!"
str2 = Hello Nowcoder!
print(str1)
print(str2);
##################################
# print默认换行,中间可以用转移符
换行
print("Hello World!
Hello Nowcoder!")
NP3 读入字符串
# python的输入input()默认输入的就是字符串 str = input() print(str) ######################### # 可以直接在输入作为输出的参数 print(input())
NP4 读入整数数字
这里输出<class int> 猜测python中所有类型都封装成了类
# 将读入的字符串强转成数值型 num = int(input()) print(num) # type()函数,返回变量的类型 print(type(num))
NP5 格式化输出(一)
name = input()
# 单纯的字符串拼接
print("I am " + name + " and I am studying Python in Nowcoder!")
# 都号分割,默认每两个之间有一个空格
print("I am", name, "and I am studying Python in Nowcoder!")
# 类似于C语言的printf输出
print(I am %s and I am studying Python in Nowcoder! %name)
# .format() 默认
print(I am {} and I am studying Python in Nowcoder! .format(name))
# .format() 加上位置
print(I am {0} and I am studying Python in Nowcoder! .format(name))
# .format() 指定参数
print(I am {str} and I am studying Python in Nowcoder! .format(str = name))
# 字符串前加个f则可直接将变量嵌入输出
print(fI am {
str} and I am studying Python in Nowcoder!)
NP6 牛牛的小数输出
num = float(input())
# 用C语言式方便
print("%.2f" %num)
# f用冒号加入参数 注意冒号后不要加空格
print(f"{
num :.2f}")
# .format() 型类似
print("{:.2f}".format(num))
02 类型转换
NP7 小数化整数
fnum = float(input()) inum = int(fnum) print(inum) ################################# # 调用math的trunc()函数,截取整数部分 import math print(math.trunc(float(input())))
NP8 为整数增加小数点
num = int(input())
print("%.1f" %num)
# 直接float()也行 这样会返回一个0.0
print(type(float()))
NP9 十六进制数字的大小
# python没有字符型变量,至于长度为1的字符串 num = input() # 第二个参数指定进制 print(int(num, 16))
03 字符串
NP10 牛牛最好的朋友们
str1 = input() str2 = input() print(str1 + str2)
NP11 单词的长度
str = input() # len函数 print(len(str)) # 类函数__len__() print(str.__len__())
NP12 格式化输出(二)
name = input() # 首字母大写 print(name.lower()) # 全大写 print(name.upper()) # 全小写 print(name.title())
NP13 格式化输出(三)
str = input() # 去除两侧的空格 print(str.strip())
NP14 不用循环语句的重复输出
str = input() # 直接用*复制 print(str * 100)
NP15 截取用户名前10位
str = input() # [begin, end) print(str[0 : 10]) # 默认从0开始 print(str[: 10])
04 列表
NP16 发送offer
list = ["Allen", "Tom"]
for str in list :
print("{s}, you have passed our interview and will soon become a member of our company." .format(s = str))
# 移除
list.remove("Tom")
# 末尾添加
list.append("Andy")
for str in list :
print("%s, welcome to join us!" %str)
########################
# 多行字符串 ,这个居然不能过
print(Allen, you have passed our interview and will soon become a member of our company.
Andy, you have passed our interview and will soon become a member of our company.
Allen, welcome to join us!
Andy, welcome to join us!)
NP17 生成列表
str = input(); # 分割,默认按照空格生成列表 print(str.split()) # 可以添加分割的参数 print(str.split( ))
NP18 生成数字列表
# 分割出来默认式字符串,本题要数字 arr = [int(x) for x in input().split()] print(arr)
NP19 列表的长度
list = input().split() # len函数 print(len(list)) # 内置__len__() print(list.__len__())
NP20 增加派对名单(一)
list = input().split()
list.append("Allen")
print(list)
NP21 增加派对名单(二)
list = input().split() # insert(位置, 内容) list.insert(0, "Allen") print(list)
NP22 删除简历
myList = input().split() # 删除第一个 del myList[0] # [begin, end) # del myList[0 : 1] # 指定移除 #myList.remove(myList[0]) print(myList)
NP23 删除好友
list = input().split() str = input() # 指定移除 # myList.remove(str) # index(data, begin, end) idx = list.index(str) del list[idx] print(list)
NP24 淘汰排名最后的学生
myList = input().split() # 切片 负数表示倒着来 del myList[-3 : ] print(myList) ################# # 指定倒数输出的位置 print(lis[:-3])
NP25 有序的列表
my_list = [x for x in "Python"] # sorted不改变远列表,有返回值 print(sorted(my_list)) print(my_list) print(sorted(my_list, reverse = True))
NP26 牛牛的反转列表
num = [3, 5, 9, 0, 1, 9, 0, 3] # reversed()函数 print(list(reversed(num))) ################# # 步长为-1,表示倒着 print(num[::-1])
NP27 朋友们的喜好
name = [Niumei, YOLO, Niu Ke Le, Mona] food = [pizza, fish, potato, beef] num = [3, 6, 0, 3] list = [] # list任何东西都能append进去 # 类似JavaScript中的一个对象 list.append(name) list.append(food) list.append(num) print(list)
NP28 密码游戏
list = [int(x) for x in input()]
# 这里的遍历是非引用型
for i in range(len(list)):
# list[i]是引用
list[i] = (list[i] + 3) % 9
# 一点计算机思维都没有
list[0], list[1], list[2], list[3] = list[2], list[3], list[0], list[1]
# 根据前面的串连接
print("".join(map(str, list)))
NP29 用列表实现栈
# 列表模拟栈 stack = [1, 2, 3, 4, 5] # pop可以指定位置 stack.pop(-1) print(stack) # 默认pop最后一个 stack.pop() print(stack) num = int(input()) stack.append(num) print(stack)
NP30 用列表实现队列
# pop(0) 或者remove queue = [1, 2, 3, 4, 5] queue.pop(0) print(queue) queue.remove(queue[0]) print(queue) num = int(input()) queue.append(num) print(queue) ########## # 用双端队列 from collections import deque queue = deque([1, 2, 3, 4, 5]) queue.popleft() print(list(queue)) queue.popleft() print(list(queue)) num = int(input()) queue.append(num) print(list(queue))
NP31 团队分组
# 就是练分片 arr = [Tom, Allen, Jane, William, Tony] print(arr[0 : 0 + 2]) print(arr[len(arr) // 2 - 1 : len(arr) // 2 - 1 + 3]) print(arr[-2: ])
05 运算符
NP32 牛牛的加减器
num1 = int(input()) num2 = int(input()) print(num1 + num2) print(num1 - num2)
NP33 乘法与幂运算
x = int(input()) y = int(input()) print(x * y) print(x y)
NP34 除法与取模运算
x = int(input())
y = int(input())
# // 整数除法
print(x // y, x % y)
# / 浮点数除法
print("%.2f" %(x / y))
NP35 朋友的年龄是否相等
# 这里用字符串比较一样 a, b = input().split() print(a == b) # 化成列表比较单个元素 list = input().split() print(list[0] == list[1])
NP36 谁的数字大
# 分割后用map函数转化成指定的类型赋值 x, y = map(int, input().split()) print(x > y) print(x < y)
NP37 不低于与不超过
x, maxx, minn = map(float, input().split()) print(x <= maxx) print(x >= minn)
NP38 牛牛的逻辑运算
x, y = map(int, input().split()) # python 中逻辑运算是用关键词 print(x and y) # 与 print(x or y) # 或 print(not x) # 非 print(not y)
NP39 字符串之间的比较
str1 = input() str2 = input() print(str1 == str2) print(str1.lower() == str2.lower())
NP40 俱乐部的成员
list = input().split() name = input() # 关键词 in print(name in list)
NP41 二进制位运算
x, y = map(int, input().split()) # 38题这么写就不行 print(x & y) print(x | y)
NP42 公式计算器
x, y, z, k = map(int, input().split()) print((x + y) * (z - k))
06 条件语句
NP43 判断布尔值
num = int(input())
# 非0即1
if num :
print("Hello World!")
else :
print("Erros!")
NP44 判断列表是否为空
my_list = []
# 判空的方式比较多
# if my_list == [] :
# if not my_list:
if len(my_list) == 0 :
print("my_list is empty!")
else :
print("my_list is not empty!")
NP45 禁止重复注册
current_users = [Niuniu, Niumei, GURR, LOLO]
new_users = [GurR, Niu Ke Le, LoLo, Tuo Rui Chi]
for name in new_users :
if name.lower() in [s.lower() for s in current_users] :
print("The user name %s has already been registered! Please change it and try again!" %name)
else :
print("Congratulations, the user name %s is available!" %name)
NP46 菜品的价格
# elif 不是 else if
# 当然本题可以用字典来写
str = input()
if str == pizza:
print(10)
elif str == rice:
print(2)
elif str == yogurt:
print(5)
else:
print(8)
NP47 牛牛的绩点
# 阅读理解题
endInput = False
sum1, sum2 = 0.0, 0.0
flag = 0.0
# 读到endInput截止
for line in iter(input, endInput):
if line == A:
flag = 4.0
elif line == B:
flag = 3.0
elif line == C:
flag = 2.0
elif line == D:
flag = 1.0
elif line == F:
flag = 0.0
else:
sum1 += float(line)
sum2 += float(line) * flag
print("%.2f" %(sum2 / sum1))
NP48 验证登录名与密码
username = input()
password = input()
if username == admis and password == Nowcoder666:
print(Welcome!)
else:
print("user id or password is not correct!")
07 循环语句
NP49 字符列表的长度
list = [P, y, t, h, o, n]
print("Here is the original list:")
print(list, end="
")
print("The number that my_list has is:")
print(len(list))
NP50 程序员节
users_list = [Niuniu, Niumei, Niu Ke Le]
# 复制列表中的每个元素
for str in users_list :
print("Hi, {A}! Welcome to Nowcoder!" .format(A = str))
print("Happy Programmers Day to everyone!")
NP51 列表的最大与最小
list = []
for num in range(10, 50 + 1) :
list.append(num)
print(list)
# 首部 尾部
print(list[0], list[-1])
NP52 累加数与平均值
arr = [int(x) for x in input().split()]
sum = sum(arr)
# 多个参数都写到%后的括号中 %()
print("%d %.1f" %(sum, sum/len(arr)))
NP53 前10个偶数
# 第三个参数是步长
my_list = [x for x in range(0, 19, 2)]
for x in my_list:
print(x)
NP54 被5整除的数字
# 根据for后面的if的布尔值生成
my_list = [x for x in range(1, 50+1) if x % 5 == 0]
for x in my_list:
print(x)
NP55 2的次方数
# 生成的时候再加工
my_list = [2x for x in range(1, 10+1) ]
for x in my_list:
print(x)
NP56 列表解析
print([x for x in range(0, 9+1)])
NP57 格式化清单
list = [apple, ice cream, watermelon, chips, hotdogs, hotpot]
while len(list):
list.pop()
print(list)
NP58 找到HR
users_list = [Niuniu, Niumei, HR, Niu Ke Le,GURR, LOLO]
for name in users_list:
if name == HR:
print(Hi, HR! Would you like to hire someone?)
else :
print(fHi, {
name}! Welcome to Nowcoder!)
NP59 提前结束的循环
list = [3, 45, 9, 8, 12, 89, 103, 42, 54, 79]
num = int(input())
for x in list :
if x == num :
break
else :
print(x)
NP60 跳过列表的某个元素
# 遍历range默认是数字
for x in range(1, 15 + 1):
if x != 13:
print(x, end= )
NP61 牛牛的矩阵相加
# 二维数组
matrix = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9]
]
num = int(input())
for i in range(len(matrix)):
for j in range(len(matrix[i])):
matrix[i][j] *= num
print(matrix)
# print([[x*num for x in i] for i in [[1,2,3],[4,5,6],[7,8,9]] ])
08 元组
NP62 运动会双人项目
str1 = input() str2 = input() tup = (str1, str2) # 元组不能修改 # (NiuNiu, NiuMei) print(tup)
NP63 修改报名名单
entry_form = ("Niuniu", "Niumei")
print(entry_form)
# 异常捕获
try:
# 元组不可修改
entry_form[1] = Niukele
except TypeError:
print("The entry form cannot be modified!")
NP64 输出前三同学的成绩
tup = tuple(input().split()) print(tup[:3])
NP65 名单中出现过的人
tup = (Tom, Tony, Allen, Cydin, Lucy, Anna)
print(tup)
name = input()
if name in tup :
print("Congratulations!")
else :
print("What a pity!")
NP66 增加元组的长度
tup = tuple(range(1,6)) print(tup) print(len(tup)) # 可以用 += 猜测还是对象覆盖 tup += tuple(x for x in range(6, 10 + 1)) print(tup) print(len(tup))
09 字典
字典说白了就是键值对
NP67 遍历字典
operators_dict = {
<: less than,
==: equal
}
print("Here is the original dict:")
# 默认遍历key
for key in sorted(operators_dict) :
print("Operator %s means %s." %(key, operators_dict[key]))
# 动态添加
operators_dict[>] = greater than
print("
The dict was changed to:")
# .items() 遍历key,val
for key, val in sorted(operators_dict.items()):
print("Operator %s means %s." %(key, val))
NP68 毕业生就业调查
survey_list = [Niumei, Niu Ke Le, GURR, LOLO]
result_dict = {
Niumei: Nowcoder,
GURR: HUAWEI
}
for name in survey_list :
# 根据key来in
if name in result_dict:
print("Hi, %s! Thank you for participating in our graduation survey!" %name)
else :
print("Hi, {}! Could you take part in our graduation survey?" .format(name))
NP69 姓名与学号
my_dict_1 = {
name: Niuniu, Student ID: 1}
my_dict_2 = {
name: Niumei, Student ID: 2}
my_dict_3 = {
name: Niu Ke Le, Student ID: 3}
dict_list = []
dict_list.append(my_dict_1)
dict_list.append(my_dict_2)
dict_list.append(my_dict_3)
for it in dict_list:
print("%ss student id is %d." %(it["name"], it["Student ID"]))
NP70 首都
# 键值对套键值对
cities_dict = {
Beijing: {
Capital: China},
Moscow: {
Capital: Russia},
Paris: {
Capital: France}
}
for it in sorted(cities_dict) :
print(f"{
it} is the capital of {
cities_dict[it][Capital]}!")
NP71 喜欢的颜色
result_dict = {
Allen: [red, blue, yellow],
Tom: [green, white, blue],
Andy: [black, pink]
}
# 指定遍历key
for it in sorted(result_dict.keys()):
print(f"{
it}s favorite colors are:")
for color in result_dict[it]:
print(color)
NP72 生成字典
name = input().split() language = input().split() # zip() 函数 word = dict(zip(name, language)) print(word)
NP73 查字典
words = {
a: [apple, abandon, ant],
b: [banana, bee, become],
c: [cat, come],
d: [down]
}
str = input()
for word in words[str]:
print(word, end=" ")
NP74 字典新增
letter = input()
word = input()
words = {
"a": ["apple", "abandon", "ant"],
"b": ["banana", "bee", "become"],
"c": ["cat", "come"],
"d": "down",
# 最后的,可加可不加
letter: word,
}
print(words)
NP75 使用字典计数
str = input()
word = {
}
for ch in str :
# 也可以用in判断
try :
word[ch] += 1
except :
# 初始必须设置值
word[ch] = 1
print(word)
10 内置函数
NP76 列表的最值运算
arr = [int(x) for x in input().split()] print(max(arr)) print(min(arr))
NP77 朋友的年龄和
arr = [int(x) for x in input().split()] print(sum(arr))
NP78 正数输出器
# 然而0不算正数 print(abs(int(input())))
NP79 字母转数字
# ord 十进制 print(ord(input()))
NP80 数字的十六进制
# hex 十六进制 print(hex(int(input())))
NP81 数字的二进制表示
# bin 二进制 print(bin(int(input())))
NP82 数学幂运算
x, y = map(int, input().split()) print(x y) print(pow(y, x))
NP83 错误出现的次数
list = input().split() print(list.count(0))
NP84 列表中第一次出现的位置
list = input().split() # 不存在返回非法值 print(list.index(NiuNiu))
NP85 字符的类型比较
str = input() print(str.isalpha()) print(str.isdigit()) print(str.isspace())
NP86 字符子串的查找
long_str = input() # 三个参数指定搜索范围,一个参数默认全范围 print(long_str.find(NiuNiu, 0, len(long_str)))
NP87 子串的数量
str = input() print(str.count(Niu, 0, len(str)))
NP88 句子拆分
# 默认分割成字符串 print(input().split())
NP89 单词造句
arr = []
endstr = 0
# 直到endstr位置,每行接收的东西
for line in iter(input, endstr):
arr.append(line)
print(" ".join(arr))
NP90 修正错误的字母
str = input();
# 默认全部替换
print(str.replace("a*", "ab"))
# 指定,最多替换cnt次
# print(str.replace("a*", "ab", cnt))
NP91 小数位修正
num = float(input()) # 四舍五入保留至最多两位小数 print(round(num, 2))
NP92 公式计算器
str = input() # 根据表达式计算 这个挺强大的 print(eval(str))
NP93 创建集合
st = set(input().split()) print(sorted(st))
11 面向对象
NP94 函数求差
# 可以不指点类型和返回值
# 不return的话默认返回None
def cal(a, b) :
return a - b
x = int(input())
y = int(input())
print(cal(x, y))
print(cal(y, x))
NP95 兔子的数量
# 指定参数类型和返回值
def fib(n : int) -> int :
if n <= 2 :
return n + 1
else :
return fib(n-1) + fib(n-2)
n = int(input())
print(fib(n))
NP96 球的表面积
import math
def calBall(n) :
# 需要导入math包
# pow可以不用math.
return 4 * math.pi * math.pow(n, 2)
arr = [1,2,4,9,10,13]
for num in arr :
print("%.2f" %calBall(num))
NP97 班级管理
name = input()
id = input()
score = int(input())
list = input().split()
print("%ss student number is %s, and his grade is %d. He submitted %d assignments, each with a grade of " %(name, id, score, len(list)) , end="")
for ch in list :
print(ch, end=" ")
NP98 修改属性1
class Employee():
# 构造
def __init__(self, name: str, salary: int):
self.name = name
self.salary = salary
# 第一个参数必须是self 当然可以写成别的名称
def setAge(self, age: int):
self.age = age
def printclass(self):
try:
print("%ssalary is %d, and his age is %d" %
(self.name, self.salary, self.age))
except:
print("Error! No age")
name = input()
salary = int(input())
e = Employee(name, salary)
e.printclass()
age = int(input())
e.setAge(age)
e.printclass()
NP99 修改属性2
class Employee():
def __init__(self, name: str, salary: int):
self.name = name
self.salary = salary
def printclass(self):
print("%ssalary is %d, and his age is %d" %
(self.name, self.salary, self.age))
name = input()
salary = int(input())
age = int(input())
e = Employee(name, salary)
# hasattr 是否有该成员变量
print(hasattr(e, age))
if not hasattr(e, age):
# 添加成员变量
setattr(e, age, age)
e.printclass()
NP100 重载运算
class Coordinate():
x, y = 0, 0
def __init__(self, x: int, y: int):
self.x = x
self.y = y
# to_string 重载
def __str__(self):
return "(" + str(self.x) + ", " + str(self.y) + ")"
# 根据需求返回lhs还是rhs还是新值
def __add__(self, rhs):
return Coordinate(self.x + rhs.x, self.y + rhs.y)
x1, y1= map(int, input().split())
point1 = Coordinate(x1, y1)
x2, y2= map(int, input().split())
point2 = Coordinate(x2, y2)
point3 = point1 + point2
print(point3)
12 正则表达式
正则表达之我不熟悉,基本都是cv的
NP101 正则查找网址
import re cmp = https://www str = input() # 从开头匹配到第一位不匹配的范围 # 元组的形式 print(re.match(cmp, str).span())
NP102 提取数字电话
import re str = input() # r表示纯字符串 # 全部数字信息 # 0-9的数字 print(re.sub(r[^0-9], , str)) # D 等价于 数字 # d 等价于 非数字 print(re.sub(rD, , str))
NP103 截断电话号码
import re str = input() # 提取的仅包含数字和-的电话号码 res = re.match(r[0-9|-]*, str) print(res.group())
原创文章,作者:ItWorker,如若转载,请注明出处:https://blog.ytso.com/tech/pnotes/291474.html