Poj 3364 Black and white painting

Black and white painting

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 2458		Accepted: 1678

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

开始看这题有点蒙，画了各种图，没思路。回过头来重新读题。就来思路了。我把8*8格子缩为1*1格子，该格子白色就符合，黑色就不符合。9*9变成2*2....类推得n*m即为(n-8+1)*(m-8+1)的格子，然后找格子有多少白色的，就有多少棋盘了。

代码：

#include 
#include 
using namespace std;
int main()
{
    int n,m,i;
    while(scanf("%d%d%d",&n,&m,&i))
    {
        if(n == 0 && m == 0 && i == 0)
            break;
        n = n-7;
        m = m-7;
        if((n*m)%2 == 0)
        {
            cout << (n*m)/2 <