#include<bits/stdc++.h> using namespace std; int p[505],w[505],dp[505][10005]; void slove(){ int e,f,n; cin>>e>>f>>n; f-=e; for(int i=1;i<=n;i++)cin>>p[i]>>w[i]; memset(dp,0x3f3f3f3f,sizeof(dp)); dp[0][0]=0; for(int i=1;i<=n;i++)for(int j=0;j<=f;j++)for(int k=0;k*w[i]<=j;k++)dp[i][j]=min(dp[i][j],dp[i-1][j-k*w[i]]+k*p[i]); if(dp[n][f]>=0x3f3f3f3f)cout<<"This is impossible.\n"; else cout<<"The minimum amount of money in the piggy-bank is "<<dp[n][f]<<".\n"; return; } int main(){ int t; cin>>t; while(t--)slove(); return 0; }