i = 0
j = 1
sum = 0
arr =[] 
while(i < 10):
    sum = sum + j*( 1/(1 + i) )
    arr +=[ j*( 1/(1 + i) )]
    i = i + 1
    print i ,j , arr
    j = -j

i = 0 
j = 0
while(i < 10):
    i=i+1
    a = 1/i
    j = a + j
    print i , a, j

i = 0 
j = 0
while(i < 10):
    i=i+1
    j = 1/i + j
    print i , j

i = 0
j = 1
sum = 0
arr =[] 
while(i < 10):
    j = -j
    sum = sum + j*( 1/(1 + i) )
    arr +=[ j*( 1/(1 + i) )]
    i = i + 1
    print i ,j , arr

i = 0 
j = 0
check = 1
while(i < 10):
    check = check*-1
    i=i+1
    j = 1/i*check + j
    print i , j 

i = 0 
j = 0
check = 1
while(i < 10):
    i=i+1
    j = 1/i*check + j
    check = check*-1
    print i , j 

sum = 0
for i in range(1,11):
    sum = sum + 1/i
    print i , sum

sum = 0
for i in range(1,11):
    sum = sum + 1/i*(-1)^i
    print i , sum

sum = 0
for i in range(1,11):
    sum = sum + 1/i*(-1)^(i+1)
    print i , sum

L = [1,2,3,4,5,6,7,8,9,10]
want = 0
for i in range(0,len(L)):
    want += L[i]
want/len(L)