from sys import stdin
input=lambda :stdin.readline()[:-1]

mod=998244353
M=(10**5)*3 
fac=[1]*M
ninv=[1]*M
finv=[1]*M
for i in range(2,M):
  fac[i]=fac[i-1]*i%mod
  ninv[i]=(-(mod//i)*ninv[mod%i])%mod
  finv[i]=finv[i-1]*ninv[i]%mod

def binom(n,k):
  if n<0 or k<0:
    return 0
  if k>n:
    return 0
  return (fac[n]*finv[k]%mod)*finv[n-k]%mod

pow2=[1]
for _ in range(M):
  pow2.append(pow2[-1]*2%mod)


N=2*10**5+10
q=int(input())
M=int(q**0.5)+1
bucket=[[] for i in range(M)]
ans=[0]*q
for i in range(q):
  n,m=map(int,input().split())
  ans[i]=pow2[n]-1
  n-=1
  m-=1
  bucket[m*M//N].append((m,n,i))

for i in range(M):
  if i&1:
    bucket[i].sort(key=lambda x:-x[1])
  else:
    bucket[i].sort(key=lambda x:x[1])

res=1
n=1
m=0
inv2=pow(2,mod-2,mod)

for b in bucket:
  for mi,ni,i in b:
    while m<mi:
      res+=binom(n,m+1)
      res%=mod
      m+=1
    while m>mi:
      res-=binom(n,m)
      res%=mod
      m-=1
    while n<ni:
      res=2*res-binom(n,m)
      res%=mod
      n+=1
    while n>ni:
      res=inv2*(res+binom(n-1,m))
      res%=mod
      n-=1
    ans[i]*=res
    ans[i]%=mod

print(*ans,sep='\n')