import com.sun.corba.se.internal.Interceptors.PIORB;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;


/**
 *
 * @author cteam07
 */
public class ith {

    public static int pole[][];
    public static int count = 0;
    public static int now = 0;
    public static boolean started = false;
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
                
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        
        String line = br.readLine();
        int x, y, n;
        int xco, yco;
        
        while(line != null) {
            
            StringTokenizer tk = new StringTokenizer(line);
            if(tk.hasMoreTokens()) {
                
                if(tk.countTokens() == 3) {
                    
                    try{
                        x = Integer.parseInt(tk.nextToken());
                        y = Integer.parseInt(tk.nextToken());
                        n = Integer.parseInt(tk.nextToken());

                        if(x == 0 && y == 0 && n == 0) {
                            System.exit(0);
                        } else {
                            startTask(x, y, n);
                        }
                    } catch(Exception e) {}
                    
                } else if(tk.countTokens()  == 2 && started) {
                    
                    try {
                        xco = Integer.parseInt(tk.nextToken());
                        yco = Integer.parseInt(tk.nextToken());
                        insertQ(xco, yco);
                    } catch (Exception e) {}
                }
                
            }
         
            line = br.readLine();
            
        }
        
        
    }
    
    public static void startTask(int x, int y, int n) {
        
        if(x < 1 || x > 20000 || y < 1 || y > 20000 || n < 0 || n > (x*y)) {
                //System.out.println("new task refused, invalid input");
                return;
        }
        
        if(n == 0) {
            System.out.println(x*y);
        }
        
        started = true;
        pole = new int[x][y];
        count = n;
        now = 0;
    }
    
    public static void insertQ(int x, int y) {
        
        if(x < 1 || x > pole.length || y < 1 || y > pole[0].length) {
            return;
        }        
        now++;
        
        vyplnRadek(x-1);
        //debug(x-1, y-1);
        vyplnSloupec(y-1);
        //debug(x-1, y-1);
        vyplnLP(x-1, y-1);
        //debug(x-1, y-1);
        vyplnPL(x-1, y-1);
        //debug(x-1, y-1);
        
        if(count == now) {
            started = false;
            System.out.println(countFree());
        }
    }

    public static int countFree() {
        int sum = 0;
        for(int i = 0; i < pocetR(); i++) {
            for(int j = 0; j < pocetS(); j++) {
                if(pole[i][j] == 0)  sum ++;
            }
        }
        return sum;        
    }
    
   public static void debug(int x, int y) {
        for(int i = 0; i < pole.length; i++) {
            for(int j = 0; j < pole[0].length; j++) {
                if((i == x) && (j == y)) {
                    System.out.print(" X");
                }
                else {
                    System.out.print(" " + pole[i][j]);
                } 
            }
            System.out.println("");
        }
        System.out.println("");
    }
    
    
    private static int pocetR() {
        return pole.length;
    } 
    
    private static int pocetS() {
        return pole[0].length;
    }

    private static void vyplnLP(int x, int y) {
        
        int i = x-1;
        int j = y-1;
        for(; (i > -1&& j > -1); i--, j--) {
            pole[i][j] = 1;
        }
        
        i = x+1;
        j = y+1;
        for(; (i < pocetR() && j < pocetS()); i++, j++) {
            pole[i][j] = 1;
        }
        
        
    }

    private static void vyplnPL(int x, int y) {
        int i = x-1;
        int j = y+1;
        for(; (i > -1 && j < pocetS()); i--, j++) {
            pole[i][j] = 1;
        }
        
        i = x+1;
        j = y-1;
        for(; (i < pocetR() && j > -1); i++, j--) {
            pole[i][j] = 1;
        }
    }
    
    private static void vyplnRadek(int x) {
        
        for(int i = 0; i < pocetS(); i++) {
            pole[x][i] = 1;
        }
        
    }

    private static void vyplnSloupec(int y) {
        for(int i = 0; i < pocetR(); i++) {
            pole[i][y] = 1;
        }
    }
    
    

}