贪心。。 

#include<cstdio>
#include<algorithm>
#include<iostream>
#include<cmath>
#define ll long long
using namespace std;
int main()
{
    //freopen("in.txt", "r", stdin);
    ios::sync_with_stdio(false);
    int t; cin>>t;
    while(t--){
        int x, y, n;
        cin>>x>>y>>n;
        ll a=0, b= 0, c = 0, d = 0;
        int l, r;
        ll ret = 0;
        for(int i = 1; i <= n; i++){
            cin>>l>>r;
            a = l, b = r;
            c = x-l, d = y-r;
            ret += min(a, min(d, min(b, c)));
        }
        cout<<ret<<endl;
    }
    return 0;
}