Barn Construction    rocky.X

Farmer Ran wants to build a new rectangular barn on a rectangular
pasture measuring M (1 <= M <= 300) by N (1 <= N <= 300). The barn's
sides will be parallel to the pasture's boundaries. Although he has
the necessary materials to build an arbitrarily large barn, he
notices that certain parcels of land have colossal rocks that
preclude any construction upon them.

Ever the engineer, he has obtained a device which can instantly
vaporize large rocks. Its construction is such that it can operate
up to X times (0 <= X <= 90,000) before its parts give out. FR plans
to clear some land with this device and then build the largest
rectangular barn he can using the clear land.

Determine the largest size barn FR can build after removing up to
X rocks.

PROBLEM NAME: rocky

INPUT FORMAT:

* Line 1: Three space-separated integers: N, M, and X

* Lines 2..N+1: Line i+1 describes the M parcels of row i with M
        space-separated integers that indicate respectively whether a
        rock is present in each column. '1' indicates that the
        position has a rock; '0' indicates that the position is clear.
        The first integer on the line describes column 1, and so on.

SAMPLE INPUT:

3 5 1
0 0 0 0 1
0 1 0 0 0
0 0 0 1 0

INPUT DETAILS:

FJ can remove at most one of the three rocks. 

OUTPUT FORMAT:

* Line 1: One integer: the maximum area barn that can be built after
        optimally removing rocks.

SAMPLE OUTPUT:

9

OUTPUT DETAILS:

Remove the rock at row 2, column 2. This lets FR build a 3x3 farm with a
total area of 9. He cannot do better than this.