#include<iostream>
#include<vector>
#include<algorithm>
#include<cassert>
#include<atcoder/modint>
using namespace std;
#include<array>
template<typename T,unsigned int N>
struct Matrix{
	array<array<T,N>,N>dat;
	array<T,N>&operator[](int i){return dat[i];}
	const array<T,N>&operator[](int i)const{return dat[i];}
	Matrix(){for(int i=0;i<N;i++)dat[i].fill(T(0));}
	static Matrix eye(){
		Matrix res;
		for(int i=0;i<N;i++)res[i][i]=1;
		return res;
	}
	Matrix operator+(const Matrix&A)const{
		Matrix res;
		for(int i=0;i<N;i++)for(int j=0;j<N;j++)
			res[i][j]=dat[i][j]+A[i][j];
		return res;
	}
	Matrix operator*(const Matrix&A)const{
		Matrix res;
		for(int i=0;i<N;i++)for(int k=0;k<N;k++)for(int j=0;j<N;j++)
			res[i][j]+=dat[i][k]*A[k][j];
		return res;
	}
	Matrix pow(long long n)const{
		Matrix a=*this,res=eye();
		for(;n;a=a*a,n>>=1)if(n&1)res=res*a;
		return res;
	}
};
using mint=atcoder::modint998244353;
using mat=Matrix<mint,2>;
mint naive(long N,long M)
{
	if(N>M)swap(N,M);
	assert(N<=M);
	auto f=[](long NM,long N,long M)
	{
		if(N>M)swap(N,M);
		if(NM<0)return 0L;
		else if(NM<=N)return NM+1;
		else if(NM<=M)return N+1L;
		else if(NM<=N+M)return N+M-NM+1;
		else return 0L;
	};
	mint cur=1,cur2=0;
	for(long i=1;i<=N+M;i++)
	{
		mint now=0;
		now+=cur*(f(i-1,N-1,M)+f(i-1,N,M-1));
		now+=cur2*f(i-2,N-1,M-1);
		cur2=cur;
		cur=now;
	}
	return cur;
}
mint naive2(long N,long M)
{
	if(N>M)swap(N,M);
	assert(N<=M);
	mat E=mat::eye();
	for(int i=0;i<N+M;i++)
	{
		mat A;
		A[0][0]=i<N?(i+1)*2:i>=M?(N+M-i)*2:N*2+1;
		A[0][1]=i<N?i:i>=M?N+M-i:N;
		A[1][0]=1;
		E=A*E;
	}
	return E[0][0];
}
mat L[10000001],R[10000001];
mint solve(long N,long M)
{
	if(N>M)swap(N,M);
	assert(N<=M);
	assert(N<=10000000);
	mat E=mat::eye();
	E=L[N]*E;
	mat A;
	A[0][0]=N*2+1;
	A[0][1]=N;
	A[1][0]=1;
	E=A.pow(M-N)*E;
	E=R[N]*E;
	return E[0][0];
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	L[0]=mat::eye();
	R[0]=mat::eye();
	for(int i=1;i<=10000000;i++)
	{
		mat A;
		A[0][0]=mint::raw(i*2);
		A[0][1]=mint::raw(i-1);
		A[1][0]=mint::raw(1);
		L[i]=A*L[i-1];
		A[0][1]=mint::raw(i);
		R[i]=R[i-1]*A;
	}
	/*
	for(long N=0;N<=20;N++)for(long M=0;M<=20;M++)
	{
		mint A=naive(N,M),B=solve(N,M);
		if(A!=B)
		{
			cout<<"WA on (N, M) = ("<<N<<", "<<M<<")"<<endl;
			cout<<"naive = "<<A.val()<<" naive2 = "<<B.val()<<endl;
			return 1;
		}
	}
	return 0;
	*/
	int T;cin>>T;
	for(;T--;)
	{
		long N,M;
		cin>>N>>M;
		cout<<solve(N,M).val()<<"\n";
	}
}