#include <iostream>

 #include <cstring>

 #include <cstdio>

 using namespace std;

 const int maxn = 1e6 + ;

 typedef long long ll;

 int value[maxn], interest[maxn];

 ll dp[maxn], ans, money, tolmoney;

 int main()

 {

     int kind, tcase, year;

     while (scanf("%d", &tcase) != EOF)

     {

         while (tcase--)

         {

             scanf("%lld%d", &money, &year);

             scanf("%d", &kind);

             for (int i = ; i < kind; i++)

             {

                 scanf("%d%d", &value[i], &interest[i]);

                 value[i] /= ;

             }

             memset(dp, , sizeof(dp));

             ans = , tolmoney = money;

             for (int j = ; j < year; j++)

             {

                 if (j != )

                     money = tolmoney;

                 money /= ;

                 for (int i = ; i < kind; i++)

                 {

                     for (int k = value[i]; k <= money; k++)

                     {

                         dp[k] = max(dp[k], dp[k-value[i]] + interest[i]);

                         ans = max(dp[k], ans);

                     }

                 }

                 tolmoney += ans;

             }

             printf("%lld\n", tolmoney);

         }

     }

     return ;

 }