Spreading Fire (Intuit India)

There is a 2D plane of size N*M. There is fire which is there at K different points in the 2D plane. From each of these K points, the fire is spreading in a circular form with the radius of the fire increasing by time. So, if at t=1, the radius of fire (represented by R) was 2, at t=2, it becomes 4, at t=3, it become 6 and so on. "t" denotes time here. Help us determine, the number of points (points are denoted by (x,y), where both x and y are whole numbers, and are within the plane) which would not be touched by the fire.

Input Format

The first line has 3 space separated integer N, M and K, dimensions of the 2D plane and the number of fire points.

Next K lines each having 2 space separated integers, stating the coordinates of the fire.

Next line denotes the R, the radius of the fire at t=1,

Next line contain an integer T, stating the time at which we want to know points not touched by fire.