Problems
Fractions: addition and subtraction
Fractions: addition and subtraction
Two fractions are given. Find their sum or difference.
\InputFile
Each line contains an example of addition or subtraction of fractions. The numerator and denominator of each fraction is a positive integer, not greater than $10^9$.
\OutputFile
For each input example, print in a separate line the answer in the form of an irreducible fraction. If the answer is negative, a minus sign in front of the fraction should be printed.
Input example #1
1/2 + 3/4 4/5 - 7/3 3/2 + 5/6 7/6 - 1/6 3/2 - 3/2
Output example #1
5/4 -23/15 7/3 1/1 0/1