#include <bits/stdc++.h>
#pragma GCC target("avx")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("no-stack-protector")
using namespace std;
const int N=200010,M=998244353,S=450;
int T,n,m,fac[N],inv[N],pw[N],csum[S][N];
int comb(int sum1,int sum2){
	if(sum1<sum2) return 0;
	return 1ll*fac[sum1]*inv[sum2]%M*inv[sum1-sum2]%M;
}
int solve(int sum1,int sum2){
	if(sum2<0) return 0;
	if(sum1%S==0) return csum[sum1/S][sum2];
	return (comb(sum1-1,sum2)+2*solve(sum1-1,sum2-1)%M)%M;
}
void work(){
	scanf("%d%d",&n,&m);
	printf("%d\n",1ll*(pw[n]-1+M)%M*solve(n-1,m-1)%M);
}
int main(){
	fac[0]=fac[1]=inv[0]=inv[1]=pw[0]=1,pw[1]=2;
	for(int i=2;i<=200000;i++){
		pw[i]=1ll*pw[i-1]*2%M;
		fac[i]=1ll*fac[i-1]*i%M;
		inv[i]=1ll*inv[M%i]*(M-M/i)%M;
	}
	for(int i=2;i<=200000;i++)
		inv[i]=1ll*inv[i-1]*inv[i]%M;
	for(int i=0;i<=200000/S;i++)
		for(int j=0;j<=i*S;j++)
			csum[i][j]=(csum[i][j-1]+comb(i*S,j))%M;
	for(scanf("%d",&T);T;T--) work();
}