#include <bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define ll long long
#define ld double
#define llu long long unsigned

int grid[20][20];
int r1 , c1;
int m , n;
vector < pair < int , int > > p;

void dfs(  )
{
    for( int k = r1 - 1 ; k <= r1 + 1 ; k++ )
    {
        for( int l = c1 ; l < m ; l++ )
        {
            if( !( k == r1 or l == c1 or k - l == r1 - c1 or k + l == r1 + c1 ) and grid[k][l] == 0 and k >= 0 and k < n and l >= 0 and k < m )
            {
                grid[k][l] = -1;
                r1 = k;
                c1 = l;
                p.push_back( make_pair( k , l ) );
                return;
            }
        }
        for( int l = c1 ; l >= 0 ; l-- )
        {
            if( !( k == r1 or l == c1 or k - l == r1 - c1 or k + l == r1 + c1 ) and grid[k][l] == 0 and k >= 0 and k < n and l >= 0 and k < m )
            {
                grid[k][l] = -1;
                r1 = k;
                c1 = l;
                p.push_back( make_pair( k , l ) );
                return;
            }
        }
    }
    for( int k = c1 - 1 ; k <= c1 + 1 ; k++ )
    {
        for( int l = r1 ; l < n ; l++ )
        {
            if( !( l == r1 or k == c1 or l - k == r1 - c1 or k + l == r1 + c1 ) and grid[k][l] == 0 and k >= 0 and k < n and l >= 0 and k < m )
            {
                grid[l][k] = -1;
                r1 = l;
                c1 = k;
                p.push_back( make_pair( l , k ) );
                return;
            }
        }
        for( int l = r1 ; l >= 0 ; l-- )
        {
            if( !( l == r1 or k == c1 or l - k == r1 - c1 or k + l == r1 + c1 ) and grid[k][l] == 0 and k >= 0 and k < n and l >= 0 and k < m )
            {
                grid[l][k] = -1;
                r1 = l;
                c1 = k;
                p.push_back( make_pair( l , k ) );
                return;
            }
        }
    }
}

int main()
{
    fast;
    int t;
    cin>>t;
    for( int c = 1 ; c <= t ; c++ )
    {
        cout<<"Case #"<<c<<": ";
        cin>>n>>m;
        memset( grid , 0 , sizeof( grid ) );
        p.clear();
        p.push_back( make_pair( 0 , 0 ) );
        r1 = 0 ;
        c1 = 0 ;
        grid[0][0] = -1;
        for( int tt = 1 ; tt <= m * n ; tt++ )
            dfs(  );
//        cout<<p.size()<<endl;
//        for( int tt = 0 ; tt < p.size() ; tt++ )
//                cout<<p[tt].first+1<<" "<<p[tt].second+1<<endl;
        if( p.size() == m * n )
        {
            cout<<"POSSIBLE\n";
            for( int tt = 0 ; tt < m * n ; tt++ )
                cout<<p[tt].first+1<<" "<<p[tt].second+1<<endl;
        }
        else
            cout<<"IMPOSSIBLE\n";
    }
    return 0;
}