Python习题week1

知识点1：

输入变为浮点数：score = input("请输入成绩：")
 score = float(score)

1题目：利用条件运算符的嵌套来完成此题：学习成绩>=90分的同学用A表示，60-89分之间的用B表示，60分以下的用C表示。

"""
File: 4学习成绩等级.py
Author: chde_wang
Date: 2020-07-22-23-16
Description:判断学生成绩等级
"""
score = input("请输入成绩：")
grade = ""
try:
    score = float(score)
    if score > 100:
        print("您输入的成绩不合法！")
    elif score >= 90:
        grade = "A"
        print('该成绩等级为：', grade)
    # elif score >= 60 and score <= 89:
    elif 60 <= score <= 89:
        grade = "B"
        print('该成绩等级为：', grade)
    else:
        grade = "C"
        print('该成绩等级为：', grade)
except ValueError:
    print("您输入的不是数字！")

没有考虑分数小于0:，修改：

"""
File: 4学习成绩等级.py
Author: chde_wang
Date: 2020-07-22-23-16
Description:判断学生成绩等级
"""
score = input("请输入成绩：")
grade = ""
try:
    score = float(score)
    if score > 100 or score < 0:
        print("您输入的成绩不合法！")
    elif score >= 90:
        grade = "A"
        print('该成绩等级为：', grade)
    # elif score >= 60 and score <= 89:
    elif 60 <= score <= 89:
        grade = "B"
        print('该成绩等级为：', grade)
    else:
        grade = "C"
        print('该成绩等级为：', grade)
except ValueError:
    print("您输入的不是数字！")

2题目：输入一行字符，分别统计出其中英文字母、空格、数字和其它字符的个数。

"""
File: 统计个数.py
Author: chde_wang
Date: 2020-07-22
Description:统计字母、数字、空格、其他个数
"""
s = input()
sum_character = 0
sum_space = 0
sum_num = 0
sum_other = 0
# 求ASCII码 ord()
# 转字符 chr()
for i in s:
    i = ord(i)
    if (65 <= i <= 97) or (97 <= i <= 122):  # 大小写
        sum_character = sum_character+1
    elif 48 <= i <= 57:
        sum_num = sum_num+1
    elif i == 32:
        sum_space = sum_space+1
    else:
        sum_other = sum_other+1
print("sum_character:", sum_character)
print("sum_num", sum_num)
print("sum_space", sum_space)
print("sum_other", sum_other)

3题目：一球从100米高度自由落下，每次落地后反跳回原高度的一半；再落下，求它在第10次落地时，共经过多少米？第10次反弹多高？

"""
File: 1乒乓球弹跳.py
Author: chde_wang
Date: 2020-07-20
Description:一球从100米高度自由落下，每次落地后反跳回原高度的一半，
     再落下，求它在第10次落地时，共经过多少米，第10次反弹多高？
"""
# 原思路
'''
height=100
sum_height_lst=[]
for i in range(10):
    sum_height_lst.append(height)  只弹跳了9次
    height=height/2
sum_height=0
for i in sum_height_lst:
    print(i)
    sum_height=sum_height+i
print(sum_height)
print(sum_height_lst[-1])
'''
# 仔细考虑之后，从第二次之后开始弹跳 总高度为弹跳的二倍
height = 100
sum_height_lst = []
for i in range(11):
    sum_height_lst.append(height)
    height = height/2
sum_height = 0
for i in range(len(sum_height_lst)):
    print(sum_height_lst[i])
for i in range(len(sum_height_lst)):
    print(sum_height_lst[i])
    if i == 0:
        sum_height = sum_height_lst[i]+sum_height
        print("第", i, "次,", "高度为：", sum_height)
    else:
        sum_height = sum_height_lst[i]*2 + sum_height
        print("第", i, "次,", "高度为：", sum_height)
print(sum_height)
print(sum_height_lst[-1])

修改：

# 仔细考虑之后，从第二次之后开始弹跳 总高度为弹跳的二倍
# 第一次的球经过的高度为100
# 从第二次后 球经过的高度为 弹跳距离的二倍
# 球第二次经过的高度为球的第一次弹跳
# 所以球第十次经过高度后为 球的第9次弹跳
# 所以还需要再弹跳一次
height = 100
sum_height_lst = []
for i in range(10):
    sum_height_lst.append(height)
    height = height/2
sum_height = 0
for i in range(len(sum_height_lst)):
    if i == 0:
        sum_height = sum_height_lst[i]+sum_height
        print("第", i+1, "次,", "弹跳高度为：", sum_height_lst[i], "总高度为：", sum_height)
    else:
        sum_height = sum_height_lst[i]*2 + sum_height
        print("第", i+1, "次,", "弹跳高度为：", sum_height_lst[i], "总高度为：", sum_height)
print(sum_height)
print(sum_height_lst[-1]/2)

网上代码：

# -*- coding: utf-8 -*-
far = []
high = 100
for i in range(1, 11):
    if i == 1:
        far.append(high)
    else:
        far.append(high * 2)
    high = high / 2

print(f'经过的总距离：far = {sum(far)}')
print(f'第十次反弹多高：high = {high}')
# --------------------------------------------------------
# 经过的总距离：far = 299.609375
# 第十次反弹多高：high = 0.09765625 

4题目：两个乒乓球队进行比赛，各出三人。甲队为a,b,c三人，乙队为x,y,z三人。已抽签决定比赛名单。有人向队员打听比赛的名单。a说他不和x比，c说他不和x,z比，请编程序找出三队赛手的名单。

"""
 File: 2比赛对抗.py
 Author: chde_wang
 Date: 2020-07-21
 Description: a不和x比赛，c不和x、z比赛
"""
import copy
list_jia = ['a', 'b', 'c']
list_yi = ['x', 'y', 'z']
list_a = copy.copy(list_yi)
list_b = copy.copy(list_yi)
list_c = copy.copy(list_yi)
# list_a=list_b=list_c=list_yi # 此处为深拷贝（拷贝地址）
for i in list_jia:
    for j in list_yi:
        if i == 'a' and j == 'x':
            list_a.remove('x')   # pop(index)  若没有index则默认为列表最后一个
        elif i == 'c':
            if j == 'x':
                list_c.remove('x')
            elif j == 'z':
                list_c.remove('z')
while len(list_yi) != 0:
    if len(list_a) == 1:
        print("a:", list_a[0])
        list_yi.remove(list_a[0])
        if list_a[0] in list_b:
            list_b.remove(list_a[0])
        if list_a[0] in list_c:
            list_c.remove(list_a[0])
        list_a.pop()
    elif len(list_b) == 1:
        print("b:", list_b[0])
        list_yi.remove(list_b[0])
        if list_b[0] in list_a:
            list_a.remove(list_b[0])
        if list_b[0] in list_c:
            list_c.remove(list_b[0])
        list_b.pop()
    elif len(list_c) == 1:
        print("c:", list_c[0])
        list_yi.remove(list_c[0])
        if list_c[0] in list_a:
            list_a.remove(list_c[0])
        if list_c[0] in list_b:
            list_b.remove(list_c[0])
        list_c.pop()

5题目：打印出如下图案（菱形）:

   *
  ***
 *****
*******
 *****
  ***
   *

'''
 打印菱形 
 前半部分和后半部分相同 倒序输出即可
 考虑空格数和星号数的关系
'''

len_lx = 7  # 菱形宽度
for i in range(1, len_lx, 2):
    len_space = (len_lx-i) // 2    # /为除法  //为整除  %取模
    print(' '*len_space, end='')
    print('*'*i, end='')
    print(' '*len_space)
for i in range(len_lx,0,-2):
    len_space = (len_lx - i) // 2
    print(' ' * len_space, end='')
    print('*' * i, end='')
    print(' ' * len_space)