#include <bits/stdc++.h>
#define int long long
using namespace std;

const int N = 2e5 + 5;
const int mod = 998244353;

int inv[N], fac[N], pw[N];

int qpow ( int x, int p = mod - 2 ) {
  int res = 1;
  while ( p ) {
    if ( p & 1 ) res = res * x % mod;
    x = x * x % mod;
    p >>= 1; 
  }
  return res;
}

int choose ( int n, int m ) {
  return fac[n] * inv[m] % mod * inv[n - m] % mod;
}

int pls ( int x, int y ) {
  return x + y >= mod ? x + y - mod : x + y;
}

signed main ( ) {
  int t; cin >> t; pw[0] = fac[0] = inv[0] = 1;
  for ( int i = 1; i <= 200000; i ++ ) fac[i] = fac[i - 1] * i % mod, inv[i] = qpow ( fac[i] );
  for ( int i = 1; i <= 200000; i ++ ) pw[i] = pls ( pw[i - 1], pw[i - 1] );
  while ( t -- ) {
    int n, m, ans = 0; cin >> n >> m;
    for ( int i = 0; i < m; i ++ ) ans = ( ans + choose ( n - 1, i ) ) % mod ;
    cout << ( ans * ( pw[n] - 1 ) % mod + mod ) % mod << "\n";
  }
}