In general, polynomials are represented in the form (see the figure on right)

where there are variables with different non-negative integer exponents and each is multiplied with a coefficient. Polynomials involve only the operations of addition, subtraction, and multiplication.

e.g. the following is a quadratic polynomial (of variable x),
   2x2 - 4x + 7
which can be represented in the form
   2 2 -4 1 7 0

Question: Write a program that accepts two polynomils and returns sum of them.

Input specification
You will be first given two integers (n and m) where n is the length of the first and m is the length of the second polynomial.
The second line will contain n number pairs (coefficient and exponent) for the first polynomial. And, the third line will contain m number pairs for the second polynomial where 1 ≤ (n, m) ≤ 20 and coefficients are between -1000 and 1000 and exponents are between 0 and 20.
Note: Polynomials can be in any order.

Output specification
Show the resulting polynomial in descending order exponents.
 Note: Show information for any coefficient different than 0.