10703.cpp

#include <bits/stdc++.h>
using namespace std;
void swap(int* p, int* q) {
    int* t;
    *t = *p;
    *p = *q;
    *q = *p;
}
int main() {
    bool a[510][510];
    int i, j, x1, y1, sum, k, h, l, x, n, y;
    while (scanf("%d %d %d", &k, &h, &n)) {
        if (k == 0 && h == 0 && n == 0) return 0;
        memset(a, 1, sizeof(a));
        while (n--) {
            scanf("%d%d%d%d", &x, &y, &x1, &y1);
            if (x1 < x) swap(x, x1);
            if (y1 < y) swap(y, y1);
            for (i = x; i <= x1; i++)
                for (j = y; j <= y1; j++) a[i][j] = 0;
        }
        sum = 0;
        for (i = 1; i <= k; i++)
            for (j = 1; j <= h; j++) {
                if (a[i][j]) sum++;
            }
        if (sum == 0)
            puts("There is no empty spots.");
        else if (sum == 1)
            puts("There is one empty spot.");
        else
            printf("There are %d empty spots.\n", sum);
    }
    return 0;
}