第三次课后题

1.

import random

i = 0
true_num = 0


while True:

	x = input("是否答题，请输入y或者n:")
	if x=="y":
		i+=1
		plus_num1 = random.randint(1,10)
		plus_num2 = random.randint(1,10)

		print("%d+%d=" %(plus_num1,plus_num2))
		answer=int(input("请输入答案："))

		if answer==(plus_num1+plus_num2):
			print('正确')
			true_num+=1
		else:	
			print('错误')
	else:
		break
true_rate = true_num/i
print("题目总数为%d,正确的数量为%d,正确率为%.2f" %(i,true_num,true_rate))

2.

import random


for i in range(10):
    num_1 = random.randint(0, 100)
    num_2 = random.randint(0, 100)
    flag = random.randint(0, 3)
    li = ['+', '*', '/', '-']
    print("%d %s %d =" %(num_1,li[flag],num_2))
    answer = str(num_1) + li[flag] + str(num_2)
    answers = eval(answer)
    inanswer = int(input('a:'))
    if inanswer == answers:
        print("right")
    else:
        print('false')

3.

n = int(input('input one number:'))
sum = 0
for i in range(1,n):
    if n%i == 0:
        sum = sum + i
if sum == n:
    print('%d是完全数' %n)
else:
    print('%d不是完全数' %n)


for j in range(2,n):
    if n%j == 0:
        print('%d不是素数' %n)
        break
else:
    print('%d是素数' %n)

t = str(n)
if t == t[::-1]:
    print('是回文数')
else:
    print('不是回文数')

4.

t_1 = sum(range(1,10))
t_2 = sum(range(1,10,2))-sum(range(2,10,2))
t_3 = 0
t_4 = 0
num = 1
for i in range(1,10):
    if i%2 == 0:
        t_3 = t_3 - (1/i)
    else:
        t_3 = t_3 + (1/i)
for j in range(1,10):
    num
    num = num*j
    if j%2 == 0:
        t_4 = t_4 - num
    else:
        t_4 = t_4 + num

print(t_1)
print(t_2)
print(t_3)
print(t_4)

5.

flag = 0
i = 0.00008


while i <= 8848.13:
    i = i * 2
    flag = flag + 1
print(flag)    

6.

for i in range(1,10):
    for j in range(i,10):
        print("  %d x %d = %d ".lstrip() %(i,j,i*j),end='   ')
    print()