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

using ll = long long;

#define TYPE_OF( VAR ) remove_const<remove_reference<decltype( VAR )>::type >::type
#define UNTIE ios_base::sync_with_stdio( false ); cin.tie( nullptr ) 
#define CIN( LL , A ) LL A; cin >> A 
#define ASSERT( A , MIN , MAX ) assert( MIN <= A && A <= MAX ) 
#define CIN_ASSERT( A , MIN , MAX ) CIN( TYPE_OF( MAX ) , A ); ASSERT( A , MIN , MAX ) 
#define FOR( VAR , INITIAL , FINAL_PLUS_ONE ) for( TYPE_OF( FINAL_PLUS_ONE ) VAR = INITIAL ; VAR < FINAL_PLUS_ONE ; VAR ++ ) 
#define FOREQ( VAR , INITIAL , FINAL ) for( TYPE_OF( FINAL ) VAR = INITIAL ; VAR <= FINAL ; VAR ++ )  
#define REPEAT( HOW_MANY_TIMES ) FOR( VARIABLE_FOR_REPEAT , 0 , HOW_MANY_TIMES ) 
#define QUIT return 0 
#define RETURN( ANSWER ) cout << ( ANSWER ) << "\n"; QUIT 

#define POWER( ANSWER , VAR , EXPONENT_REF , MODULO )			\
  TYPE_OF( VAR ) ANSWER = 1;						\
  {									\
    TYPE_OF( VAR ) VARIABLE_FOR_SQUARE_FOR_POWER = VAR;			\
    while( EXPONENT_REF != 0 ){						\
      if( EXPONENT_REF % 2 == 1 ){					\
	ANSWER = ( ANSWER * VARIABLE_FOR_SQUARE_FOR_POWER ) % MODULO;	\
      }									\
      VARIABLE_FOR_SQUARE_FOR_POWER = ( VARIABLE_FOR_SQUARE_FOR_POWER * VARIABLE_FOR_SQUARE_FOR_POWER ) % MODULO; \
      EXPONENT_REF /= 2;						\
    }									\
  }									\


#define CHECK_REDUNDANT_INPUT string VARIABLE_FOR_CHECK_REDUNDANT_INPUT = ""; cin >> VARIABLE_FOR_CHECK_REDUNDANT_INPUT; assert( VARIABLE_FOR_CHECK_REDUNDANT_INPUT == "" ); assert( ! cin );

int main()
{
  constexpr const ll bound = 1000000;
  CIN_ASSERT( N , 1 , bound );
  CIN_ASSERT( M , 1 , bound );
  CHECK_REDUNDANT_INPUT;
  ll a = M / N;
  ll b = M % N;
  constexpr const ll P = 998244353;
  ll inv[bound+1];
  inv[1] = 1;
  FOREQ( i , 2 , bound ){
    inv[i] = P - ( ( inv[ P % i ] * ( P / i ) ) % P );
  }
  ll answer = 1;
  FOREQ( i , a + 1 , M ){
    answer = ( answer * i ) % P;
  }
  ll prod_inv = 1;
  FOREQ( i , 2 , a ){
   prod_inv = ( prod_inv * inv[i] ) % P;
  }
  N--;
  POWER( prod_inv_power , prod_inv , N , P );
  answer = ( answer * prod_inv_power ) % P;
  ll& inv_a_plus = inv[a + 1];
  POWER( inv_a_plus_power , inv_a_plus , b , P );
  answer = ( answer * inv_a_plus_power ) % P;
  RETURN( answer );
}