#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(a) a.begin(),a.end()
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef unsigned long long ull;
typedef vector<int> vi;
void solve(){
int n,m; cin >> n >> m;
int mtp = 1;
if(n > m) swap(n,m), mtp = -1;
int a = (int) 1e9/n;
if(n==m){
cout << n-1 << '\n';
for(int i = 1; i < n; i++)
cout << "1 ";
cout << '\n';
}else{
if(m%n==0){
cout << m-1 << '\n';
for(int i = 1; i < m; i++)
cout << -mtp << ' ';
cout << '\n';
}else{
cout << m << '\n';
for(int i = 1; i <= m; i++)
if(i%n==0) cout << -((n-1)*a+1)*mtp << ' ';
else cout << a*mtp << ' ';
cout << '\n';
}
}
}
signed main(){
cin.tie(0)->sync_with_stdio(0);
int t = 1;
cin >> t;
while(t--){solve();}
}
