Black and White Painting

You are visiting an art museum full of modern paintings. One painting consists solely of black and white squares arranged in rows and columns like a chessboard, so that no two squares that share an edge have the same colour.

Because you are bored, you start to wonder how many $8 \times 8$ chessboards are embedded within this painting. Here an embedded $8 \times 8$ chessboard is any block of $8$ consecutive rows and $8$ consecutive columns of the painting, and its bottom-right corner square must always be white.

The input contains several test cases. Each test case is a single line with three integers $n$, $m$ and $c$ ($8 \le n, m \le 40000$): $n$ is the number of rows of the painting and $m$ is the number of columns. The value $c$ is $0$ or $1$, where $0$ means the bottom-right corner square of the painting is black and $1$ means that corner square is white.

The last test case is followed by a line containing three zeros, which is not part of the input and must not be processed.

For each test case, print on its own line the number of $8 \times 8$ chessboards embedded within the given painting — that is, the number of blocks of $8$ consecutive rows and $8$ consecutive columns whose bottom-right corner square is white.