#include <bits/stdc++.h>
#define int long long
#define gcd(x, y) __gcd(x,y)
#define IOS cin.tie(0),cout.tie(0)->sync_with_stdio(0)
#define qwq 0
#define ldb long double
using namespace std;
namespace FastIO{
//	#define _gc() (St==Ed&&(Ed=(St=in)+fread(in,1,N,stdin),St==Ed)?EOF:*St++)
#define _gc() getchar()
#define _fl() (fwrite(ot,1,now-ot,stdout))
#define _pc(x) (now==ot+N&&(_fl(),now=ot),*now++=(x))
	const int N=1<<20;char in[N],*St=in,*Ed=in,ot[N],*now=ot;
	class __f{public:~__f(){_fl();}} _f;
#define TYPES template<typename T>
	class In{
	public:
#define Ipt(typ) inline In&operator>>(typ x)
		TYPES Ipt(T&){bool f=0;x=0;char c=_gc();while(c<48||c>57)f|=(c=='-'),c=_gc();while(c>=48&&c<=57)x=x*10+(c^48),c=_gc();if(c=='.'){__float128 dot=1;for(c=_gc();c>=48&&c<=57;c=_gc())x+=(c^48)*(dot*=0.1);}return x=(f?-x:x),*this;}
		Ipt(char&){while(isspace(x=_gc()));return*this;}
#define Instr(add) char c=_gc();for(;isspace(c);c=_gc());while(!isspace(c)&&~c)add,c=_gc();
#define Gline(add) char c=_gc();for(;!(c==' '||!isspace(c));c=_gc());while(c==' '||!isspace(c))add,c=_gc();
		inline In&getline(char*x){Gline((*x++)=c);return*x=0,*this;}inline In&getline(string&x){x.clear();Gline(x.push_back(c));return*this;}
		Ipt(char*){Instr((*x++)=c);return*x=0,*this;}Ipt(string&){x.clear();Instr(x.push_back(c));return*this;}Ipt(In&){return x;}
	}fin;
	TYPES inline In&getline(T&x,In&in=fin){return fin.getline(x),in;}
	class Ot{
		char buf[80];int dt=6,tp=0;public:
#define Wt(typ) inline Ot&operator<<(typ x)
			TYPES Wt(T){if(x<0)_pc('-'),x=-x;do buf[++tp]=x%10,x/=10;while(x);while(tp)_pc(buf[tp--]^48);return*this;}Wt(char){return _pc(x),*this;}
			Wt(const char*){while(*x)_pc(*(x++));return*this;}Wt(char*){return(*this)<<(const char*)x;}Wt(string){return(*this)<<x.c_str();}
			Wt(long double){snprintf(buf,sizeof(buf),"%.*Lf",dt,x);return(*this)<<buf;}Wt(Ot&){return x;}
#define OD(typ) Wt(typ){return (*this)<<(long double)x;}
			OD(double)OD(__float128)inline Ot&setdot(const int n){return dt=n,*this;}
	}fout;
	inline Ot&setdot(const int n,Ot&ot=fout){return ot.setdot(n),ot;}
} using FastIO::fin, FastIO::fout;
#define cin fin
#define cout fout
bool Mbg;
const int P(20170408);
template<int P>
struct modint {
private:
	template<typename T>
	inline static const T Down(const T&x) {return x >= P ? x - P : x;}
public:
	unsigned int v;
	modint(unsigned int v=0) : v(v%P) {}
	using mint = modint;
#define FI friend inline
	FI ostream&operator<<(ostream&o, mint v) {return o<<v.v;}
	FI istream&operator>>(istream&i, mint&v) {int x;return i>>x,v.v=Down(x%P+P),i;}
#ifdef FASTIO
	FI FastIO::In&operator>>(FastIO::In&i, mint&v) {int x; return i>>x,v.v=Down(x%P+P),i;}
	FI FastIO::Ot&operator<<(FastIO::Ot&o, mint v) {return o<<v.v;}
#endif
	FI mint operator+(mint a, mint b) {return Down(a.v + b.v);}
	FI mint operator-(mint a, mint b) {return Down(a.v - b.v + P);}
	FI mint operator*(mint a, mint b) {return 1ull * a.v * b.v % P;}
	FI mint operator/(mint a, mint b) {return a * ~b;}
	FI mint operator^(mint a, int p) {mint r=1; for(; p; p >>= 1, a = a * a) if (p & 1) r = r * a; return r;}
	FI mint operator~(mint a) {return a ^ (P - 2);}
	FI mint operator-(mint a) {return a.v ? P - a.v : 0;}
	FI mint&operator+=(mint&a, mint b) {return a=a+b;}
	FI mint&operator-=(mint&a, mint b) {return a=a-b;}
	FI mint&operator*=(mint&a, mint b) {return a=a*b;}
	FI mint&operator/=(mint&a, mint b) {return a=a/b;}
	FI mint&operator^=(mint&a, int b) {return a=a^b;}
	FI mint&operator++(mint&a) {return a += 1;}
	FI mint&operator--(mint&a) {return a -= 1;}
	FI mint operator++(mint&a, signed) {mint x=a; return ++a, x;}
	FI mint operator--(mint&a, signed) {mint x=a; return --a, x;}
	FI bool operator==(mint a, mint b) {return a.v==b.v;}
	FI bool operator!=(mint a, mint b) {return a.v!=b.v;}
};
typedef modint<998244353> mint;
const int N(2e5 + 5), sq(455);
int q;
struct Node {
	int n, m, id;
	bool operator<(Node x) {
		if (m / sq == x.m / sq) return n < x.n;
		return m < x.m;
	}
} Q[N];
mint fac[N], ifac[N], p2[N], ans[N], res=1;
void init(int x) {
	fac[0] = p2[0] = 1;
	for (int i = 1; i <= x; i++) fac[i] = fac[i - 1] * i;
	ifac[x] = 1 / fac[x];
	for (int i = x; i; i--) ifac[i - 1] = ifac[i] * i;
	for (int i = 1; i <= x; i++) p2[i] = p2[i - 1] * 2;
}
mint C(int x, int y) {return fac[x] * ifac[y] * ifac[x - y];}
void work() {
	cin >> q;
	for (int i = 1; i <= q; i++) cin >> Q[i].n >> Q[i].m, Q[i].n--, Q[i].m--, Q[i].id = i;
	sort(Q + 1, Q + q + 1);
	int m = 0, n = 0;
	for (int i = 1; i <= q; i++) {
		while (n < Q[i].n) {
			res *= 2;
			n++;
			res -= C(n - 1, m);
//			cout << res.v << ' ';
		}
//		cout << '\n';
		while (m < Q[i].m) {
			res += C(n, m + 1);
//			cout << res.v << ' ';
			m++;
		}
//		cout << '\n';
		while (m > Q[i].m) {
			res -= C(n, m);
//			cout << res.v << ' ';
			m--;
		}
//		cout << '\n';
		while (n > Q[i].n) {
			res += C(n - 1, m);
			res *= ifac[2];
//			cout << res.v << ' ';
			n--;
		}
//		cout << '\n';
		ans[Q[i].id] = res * (p2[n + 1] - 1);
	}
	for (int i = 1; i <= q; i++) cout << ans[i].v << "\n";
}
bool Med;
signed main() {
//	freopen("P8131_2.in", "r", stdin);
//	IOS;
	init(N-5);
	int T(1);
//	cin >> T;
	clock_t st = clock();
	while (T--) work();
	cerr << (clock()-st)/1.0/CLOCKS_PER_SEC << " s\n";
	cerr << (&Mbg-&Med)/1024.0/1024.0 << " MB\n";
	return qwq;
}