Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

F. Present to Mom

time limit per test

5 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputHow many stars are there in the sky? A young programmer Polycarpus can't get this question out of his head! He took a photo of the starry sky using his digital camera and now he analyzes the resulting monochrome digital picture. The picture is represented by a rectangular matrix consisting of *n* lines each containing *m* characters. A character equals '1', if the corresponding photo pixel is white and '0', if it is black.

Polycarpus thinks that he has found a star on the photo if he finds a white pixel surrounded by four side-neighboring pixels that are also white:

a star on the photo

1

111

1

Polycarpus whats to cut out a rectangular area from the photo and give his mom as a present. This area should contain no less than *k* stars. The stars can intersect, have shared white pixels on the photo. The boy will cut out the rectangular area so that its borders will be parallel to the sides of the photo and the cuts will go straight between the pixel borders.

Now Polycarpus keeps wondering how many ways there are to cut an area out of the photo so that it met the conditions given above. Help Polycarpus find this number.

Input

The first line of the input data contains three integers *n*, *m* and *k* (1 ≤ *n*, *m* ≤ 500;1 ≤ *k* ≤ *nm*). Then follow *n* lines, containing the description of the given photo as a sequence of lines. Each line contains *m* characters '0' or '1'.

Output

Print the required number of areas on the given photo.

Examples

Input

4 6 2

111000

111100

011011

000111

Output

6

Input

5 5 4

11111

11111

11111

11111

11111

Output

9

Note

We'll number the rows and columns below starting from 1, the coordinates (*p*, *q*) will denote a cell in row *p*, column *q*.

In the first sample Polycarpus should cut out any area containing a rectangle whose opposite corners lie in cells (1, 1) and (3, 4). Only rectangles with opposite corners in (1, 1) and (*x*, *y*), where *x* ≥ 3 and *y* ≥ 4 fit the conditions.

In the second sample any rectangle whose each side is no less than four, will do. The possible rectangle sizes are 4 × 4, 4 × 5, 5 × 4 and 5 × 5. Such figures can be cut in 4 ways, 2 ways, 2 ways and 1 way correspondingly.

Please do not use the %lld specificator to read or write 64-bit integers in C++. It is preferred to use cin, cout streams or the %I64d specificator.

Codeforces (c) Copyright 2010-2017 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Oct/23/2017 16:39:45 (c4).

Desktop version, switch to mobile version.

User lists

Name |
---|