Operators

#include <iostream>
#include <algorithm>
#include <string>
#define DEB printf("DEB!\n");
#define D(X) cout<<"  "<<#X": "<<X<<endl;
int N,S;
using namespace std;
bool rec(int u,int s){
    if((s-1)==N)return u==S;
    if(rec(u+s,s+1))return 1;
    return rec(u-s,s+1);
}
int main() {
    int cas;
    cin>>cas;
    while(cas--){
        cin>>N>>S;
        if(rec(1,2))
            cout<<"Possible";
        else cout<<"Impossible";
        cout<<endl;
    }
    return 0;
}