ITERATIF

total = 0
for i = 1 to  n do
if (i mod 2==0) then
total = total - 1/i
else
total = total +1/i

Penjelasan :

total = 0+1 = 1
       = 1 - 1/2 = 1/2
       = 1/2+1/3 = 5/6