package den2;

import java.util.Arrays;
import java.util.Random;
import java.util.Scanner;

public class zad_fb {
public static void read(int[][] mass,int m,int n,int k){
    Random rand= new Random();
    for (int i = 0; i < k; i++) {
        int p=rand.nextInt(m);
        int p2=rand.nextInt(n);
        if(mass[p][p2]==0){
            mass[p][p2]=1;
        }
        else{
            i--;
        }
    }
}

public static void print(int[][] mass){
    for (int i = 0; i < mass.length; i++) {
            System.out.print(Arrays.toString(mass[i]));
    }
}
public static boolean checkPulls(int[][]mass){
    for (int i = 0; i < mass.length; i++) {
        for (int j = 0; j < mass[i].length; j++) {
            if(mass[i][j]!=0) return true;
        }
    }
    return false;
}
public static int Points(int[][] mass,int m2,int n2){
    int points=0;
    if(mass[m2][n2]!=0){
    points+=100;
    mass[m2][n2]=0;
    }
    int posi,posj;
    int[][] matrix= new int[][]{{-1,0},{0,-1},{0,1},{1,0}};
    for (int i = 0; i < matrix.length; i++) {
            posi=m2+matrix[i][0];
            posj=n2+matrix[i][1];
            if(posi>=0&&posj>=0&&posi<mass.length&&posj<mass[0].length&&mass[posi][posj]!=0){
                points+=5;// брои във всички случаи
                if(mass[posi][posj]==2){
                    mass[posi][posj]=0;
                }
                else{mass[posi][posj]=2;}
        }
    }
    return points;

}
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        int m=in.nextInt();
        int n=in.nextInt();
        int[][] mass=new int[m][n];
        int k=in.nextInt();
        read(mass, m, n, k);
        print(mass);
        int m2,n2,i=0,sum=0;
        while(checkPulls(mass)&&i<20){
            m2=in.nextInt();
            n2=in.nextInt();
            sum+=Points(mass,m2, n2);
            i++;
        }
        System.out.print(sum);
in.close();
    }
}