#include<iostream>
#define SIZE 1000
#define READ(array,n) int i;for(i=0;i<n;i++) cin>>array[i];
#define MAX(array,n)  int max=array[0],pos=0;for(i=1;i<n;i++) if(array[i] >max) {max=array[i]; pos=i;}
using namespace std;
int main()
{
	int t,s=1,l,n,count,c;
	int array[SIZE];
	cin>>t;
	while(t--)
	{
		cin>>l>>n;
		READ(array,n);
        cout<<"Scenario #"<<s++<<endl;
		c=n;
		count=0;
		while(l>0)
		{
			--c;
			//if(!c)break;
			MAX(array,n);
			array[pos]=0;
			l-=max;
			++count;
		}
		if(l<=0)
			cout<<count<<endl<<endl;
		else
			cout<<"impossible"<<endl<<endl;
	}
	return 1;
}
 

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MwoxMDAgNgoxMyAxNyA0MiA5IDIzIDU3Cjk5IDYKMTMgMTcgNDIgOSAyMyA1NwoxMDAwIDMKMzE0IDE1OSAyNjU=

3
100 6
13 17 42 9 23 57
99 6
13 17 42 9 23 57
1000 3
314 159 265