#include<bits/stdc++.h>
 using namespace std;
 int main()
 {
     int c;
     scanf("%d",&c);
     while(c--)
     {
         ],w[];
         scanf("%d%d%d",&e,&f,&n);
         ; i<n; i++)
             scanf("%d%d",&p[i],&w[i]);
         ];
         ; i<=(f-e); i++)dp[i]=;
         dp[]=;
         ; i<n; i++)
             for(int j=w[i]; j<=(f-e); j++)
                 dp[j]=min(dp[j],dp[j-w[i]]+p[i]);
         )printf("This is impossible.\n");
         else printf("The minimum amount of money in the piggy-bank is %d.\n",dp[f-e]);
     }
     ;
 }