#include <cstdio>#include <cstring>#include <algorithm>using namespace std;#define inf 10000000int dp[11000];int n;int val[550],wei[550];int main(){    int cas,n;    scanf("%d",&cas);    while(cas--)    {        int w1,w2,w;        int i,j;        scanf("%d%d",&w1,&w2);        w=w2-w1;        for(i=0;i<=w;i++) dp[i]=inf;        scanf("%d",&n);        for(i=1;i<=n;i++)            scanf("%d%d",&val[i],&wei[i]);        dp[0]=0;        for(i=1;i<=n;i++)            for(j=wei[i];j<=w;j++)                dp[j]=min(dp[j],dp[j-wei[i]]+val[i]);        if(dp[w]==inf) printf("This is impossible.\n");        else printf("The minimum amount of money in the piggy-bank is %d.\n",dp[w]);    }    return 0;}