#include <stdio.h>
int main () {
	int konec = 0, x, y, n, sur1, sur2, i, volne, pomoc, a, pomoc2;
	int riadok[20000];
	int stlpec[20000];
	int diag1[20000];
	int diag2[20000];
	while (konec == 0) {
		scanf("%d %d %d", &x, &y, &n);
		if ((x == 0)&&(y == 0)&&(n == 0))
			konec = 1;
		if (konec == 0) {
			volne = x * y;
			for (i = 0; i <= 20000; i ++) {
				riadok[i] = 1;
				stlpec[i] = 1;
				diag1[i] = 1;
				diag2[i] = 1;
			}
			for (i = 1; i <= n; i++) {
				scanf("%d %d", &sur1, &sur2);
				if (riadok[sur2] == 1) {
					pomoc = 0;
					for (a = 0; a <= x; a++)
						if (stlpec[a] == 0)
							pomoc = pomoc + 1;
					for (a = (sur2 - 1); a <= (sur2 + x - 2); a++)
						if (diag1[a] == 0)
							pomoc = pomoc + 1;
					for (a = (x - sur2); a <= (x - sur2 + y - 1); a++)
						if (diag2[a] == 0)
							pomoc = pomoc + 1;
					volne = volne - y + pomoc;
					riadok[sur2] = 0;

				}
				if (stlpec[sur1] == 1) {
					pomoc = 0;
					for (a = 0; a <= y; a++)
						if (riadok[a] == 0)
							pomoc = pomoc + 1;
					for (a = (sur1 - 1); a <= (sur1 + y - 2); a++)
						if (diag1[a] == 0)
							pomoc = pomoc + 1;
					for (a = (sur1 - y + x - 1); a <= (sur1 - y + x + x - 2); a++)
						if (diag2[a] == 0)
							pomoc = pomoc + 1;
					volne = volne - x + pomoc;
					stlpec[sur1] = 0;

				}
				if (diag1[sur1+sur2-2] == 1) {
					pomoc = 0;
					if (sur1 + sur2 - 1 <= ((x+y)/2)) {
					for (a = 0; a <= (sur1 + sur2 - 2); a++) 
						if (riadok[a] == 0) 
							pomoc = pomoc + 1;
					for (a = 0; a <= (sur1 + sur2 - 2); a++)
						if ((stlpec[a] == 0))
							pomoc = pomoc + 1; 
					if (sur1 < sur2) {
						for (a = (sur1 - sur2 + x -1); a <= (sur2 - sur1 + x - 1); a = a + 2)
							if (diag2[a] == 0)
								pomoc = pomoc + 1;
					} else {
							for (a = (sur2 - sur1 + x -1); a <= (sur1 - sur2 + x - 1); a = a + 2)
							if (diag2[a] == 0)
								pomoc = pomoc + 1;
					}
					} else {
					for (a = x; a >= (sur1 + sur2 - x - y + x - 1); a--) 
						if (riadok[a] == 0) 
							pomoc = pomoc + 1;
					for (a = y; a <= (sur1 + sur2 - x - y + y - 1); a--)
						if ((stlpec[a] == 0))
							pomoc = pomoc + 1;
					if (sur1 < sur2) {
						for (a = (sur1 - sur2 + x -1); a <= (sur2 - sur1 + x - 1); a = a + 2)
							if (diag2[a] == 0)
								pomoc = pomoc + 1;
					} else {
							for (a = (sur2 - sur1 + x -1); a <= (sur1 - sur2 + x - 1); a = a + 2)
							if (diag2[a] == 0)
								pomoc = pomoc + 1;
					}
					}
					if (sur1 + sur2 > ((x + y)/2)) {
						volne = volne - ((x+y) - sur1 -sur2 + 1) + pomoc - 1;
					} else {
						volne = volne - sur1 - sur2 + 1 + pomoc - 1;
					}
					diag1[sur1+sur2-2] = 0;

				}
				if (diag2[sur1 - sur2 + x - 1] == 1) {
					pomoc = 0;
					pomoc2 = 0;
					if (sur2 >= sur1) {
					for (a = (sur2 - 1); a <= y; a++) {
						if (riadok[a] == 0) 
							pomoc = pomoc + 1;
						pomoc2 = pomoc2 + 1;
						}
					for (a = (sur1 - 1); a <= (sur1 - 2 + pomoc2); a++)
						if ((stlpec[a] == 0))
							pomoc = pomoc + 1;
					for (a = (sur1 + sur2 - 2); a <= (sur1 + sur2 - 2 + (sur1 - sur2 + x - 1)); a = a +2)
						if (diag1[a] == 0)
							pomoc = pomoc + 1;
					} else {
					pomoc = 0;
					for (a = sur1 - 1; a <= x; a++)
						if (stlpec[a] == 0) {
							pomoc = pomoc + 1;
						pomoc2 = pomoc2 + 1;
						}
					for (a = (sur2 - 1); a <= (sur2 + pomoc2 - 2); a++)
						if ((riadok[a] == 0))
							pomoc = pomoc + 1;
					for (a = (sur1 + sur2 - 2); a <= (sur1 + sur2 - 2 + (sur2 - sur1 + x - 1)); a = a +2)
						if (diag1[a] == 0)
							pomoc = pomoc + 1;
					}
					if (sur1 >= sur2) {
						volne = volne - (x - (sur1 - sur2)) + pomoc - 1;
					} else {
						volne = volne - (x + (sur1 - sur2)) + pomoc - 1;
					}
					diag2[sur1 - sur2 + x - 1] = 0;

				}
			}
			printf("%d\n", volne);
		}
	}
	return 0;
}