Homework 3

#1 统计正数和负数的个数计算平均值

a = 0
b = 0
sum = 0
d = 1
while d != 0:
    d= int(input('Enter an intenger[输入0结束]:'))
    if d > 0 : 
        a += 1
    elif d <0:
        b += 1
    sum += d
print('正数个数:%d'%a)
print('负数个数:%d'%b)
aver = sum/(a+b)
print('平均值:%f'%aver)





#2计算未来学费

a = [10000]
for i in range(14):
    c = a[i] * 1.05
    a.append(c)
    print('十四年后的学费：%.2f'%c)
    if i  == 9:
        print('总的学费：%2f'%sum(a))


#4同时被5和6整除

t =0
for i in range(100,1000):
    if i % 5 ==0 and i % 6 ==0:
        print(i,end=' ')
        t +=1
        if t%10 ==0:
            print('\n')




#5

n =0
while n**2 < 12000:
    n +=1
print(n)


m = 0
while m**3 < 12000:
    m += 1
print(m)




#6
n = 0
for i in range(1,50001,1):
    n += 1/i
print(n)


n = 0
for i in range(50001,0,1):
    n += 1/i
print(n)




#7

num = 0
for i in range(1,98,2):
    
    num += i/(i+2)
print(num)





#8

i = 1
pai = 0

while i >0:
    num = 4*((-1)**(1+i)/(2*i-1))
    i += 1
    pai += num
    if i % 10000 ==0:
        print(pai)
    elif i > 100000:
        break



#9

for i in range(1,10000):
    a = 0
    for j in range(1,i):
        if i % j ==0:
            a += j
    if i == a:
        print(i)





#10

sum = 0
for i in range(1,8):
    for j in range(1,8):
        if i != j:
            print(i,j)
            sum += 1
print(sum)





#11
def mean():
    b = 0
    for i in range(10):
        a = int(input('请输入第数字:'))
        b += a     
    mea = b/10
    print(mea)

mean()