UVA - 11231 - Black and white painting

#include <stdio.h>

int main(){
    int n,m,c;
   while(1){
       scanf("%d %d %d",&n,&m,&c);
       if(n==0 && m==0 && c==0)
            break;
        int temp=(n-7)*(m-7);
        int ans=temp/2;
        if(temp%2==1 &&c==1)
            ans++;
        printf("%d\n",ans);

    }
    return 0;
}