#include <iostream>
#include <vector>

using namespace std;

int main()
{
    int m, n, k, i, j, t, x, y, c, c1;
    vector <vector<char> >grid;
    cin >> t;
    while(t--){
        cin >> m >> n >> k;
        for(i = 0; i < m; i++){
            for(j = 0; j < n; j++){
                grid[i][j] = '.';
            }
        }
        for(i = 0; i < k; i++){
            cin >> x >> y;
            grid[x-1][y-1] = '*';
        }
        c = 0;
        c1 = 0;
        for(i = 0; i < m; i++){
            j = 0;
            while(j < n){
                while(grid[i][j] == '.'){
                    c1++;
                    j++;
                }
                if(c1 > 1)c++;
                j++;
            }
        }
        cout << c;
    }
    return 0;
}