Python第二章課本習題參考

第一題 一元二次方程式的公式解 (a !=0)：  

import math
a, b, c = eval(input('Input a, b, and c:'))
deter = b*b - 4*a*c
if deter > 0:
    answer1 = (-b + math.sqrt(deter)) / (2*a)
    answer2 = (-b - math.sqrt(deter)) / (2*a)
    print('The solution are %f and %f' %(answer1, answer2))
elif deter == 0:
    answer = -b /(2*a)
    print('The solution is %f' %(answer))
else:
    print('No solution!')

  2nd 寫一程式，輸入一個點的座標(x, y)，輸出這個點是否在圓心(0,0)，半徑8的圓的內部或外部。

import math
x, y = eval(input('Input x and y :'))
d = math.sqrt(x**2 + y**2)
if d < 8:
    print('The point (%d, %d) is inside of the circle' %(x,y))
else:
    print('The point (%d, %d) is not inside of the circle' %(x,y))

 

import random
r = random.randint(1, 100)
r3 = r % 3
r5 = r % 5
if r3 == 0 and r5 == 0 :
    print('%d 是 3 而且 也是 5 的倍數' %(r))
elif r3 != 0 and r5 != 0 :
    print('%d 不是 3 而且 也不是 5 的倍數' %(r))
elif r3 == 0:
    print('%d 是 3 的倍數' %(r))
elif r5 == 0:
    print('%d 是 5 的倍數' %(r))

 

# 將使用者輸入的十六進位的字元轉換為其十進位所對應的數值
c = input('請輸入一個字元：')
if c >= '0' and c <= '9':
    print('對應的十進位值是 %d' %(ord(c) - ord('0')))
elif c >= 'A' and c <= 'F':
    print('對應的十進位值是 %d' %(ord(c) - ord('A') + 10))
elif c >= 'a' and c <= 'f':
    print('對應的十進位值是 %d' %(ord(c) - ord('a') + 10))