### Black and white painting

#### Problem Description

You are visiting the Centre Pompidou which contains a lot of modern paintings. In particular you notice one painting which consists solely of black and white squares, arranged in rows and columns like in a chess board (no two adjacent squares have the same colour). By the way, the artist did not use the tool of problem A to create the painting.

Since you are bored, you wonder how many *8 × 8* chess boards are embedded within this painting. The bottom right corner of a chess board must always be white.

#### Input

The input contains several test cases. Each test case consists of one line with three integers **n**, **m** and **c**. (*8 ≤ n, m ≤ 40000*), where **n** is the number of rows of the painting, and **m** is the number of columns of the painting. **c** is always *0* or *1*, where *0* indicates that the bottom right corner of the painting is black, and *1* indicates that this corner is white.

The last test case is followed by a line containing three zeros.

#### Output

For each test case, print the number of chess boards embedded within the given painting.

#### Sample Input

8 8 0 8 8 1 9 9 1 40000 39999 0 0 0 0

#### Sample Output

0 1 2 799700028