Complex numbers: addition and subtraction

Two complex numbers are given. Find their sum or difference.

Input

Each line contains an example of addition or subtraction of complex numbers. The complex number is given in the format $a+bi$ or $a-bi$, where $a$ is integer, $b$ is non-negative integer. The real and imaginary part of each complex number is no more than $10^9$ by absolute value.

Output

For each input example, print in a separate line the answer.

Examples