private static long solve ( int N , long A , long B , long K ) {
  if ( A > B ) return solve ( N , B , A , K ) ;
  long [ ] fact = new long [ N + 1 ] ;
  fact [ 0 ] = 1 ;
  for ( int i = 0 ;
  i < N ;
  i ++ ) {
    fact [ i + 1 ] = fact [ i ] * ( N - i ) % M ;
  }
  long [ ] factinv = new long [ N + 1 ] ;
  factinv [ 0 ] = 1 ;
  for ( int i = 1 ;
  i <= N ;
  i ++ ) {
    factinv [ i ] = factinv [ i - 1 ] * inverse ( i , M ) % M ;
  }
  long res = 0 ;
  for ( int i = 0 ;
  i <= Math . min ( N , K / B ) ;
  i ++ ) {
    if ( ( K - B * i ) % A == 0 ) {
      long j = ( K - B * i ) / A ;
      if ( j > N ) continue ;
      int jj = ( int ) j ;
      long c = fact [ i ] * factinv [ i ] % M ;
      c *= fact [ jj ] * factinv [ jj ] % M ;
      res += c % M ;
      res %= M ;
    }
  }
  return res ;
}

private static long solve ( int N , long A , long B , long K ) { if ( A > B ) return solve ( N , B , A , K ) ; long [ ] fact = new long [ N + 1 ] ; fact [ 0 ] = 1 ; for ( int i = 0 ; i < N ; i ++ ) { fact [ i + 1 ] = fact [ i ] * ( N - i ) % M ; } long [ ] factinv = new long [ N + 1 ] ; factinv [ 0 ] = 1 ; for ( int i = 1 ; i <= N ; i ++ ) { factinv [ i ] = factinv [ i - 1 ] * inverse ( i , M ) % M ; } long res = 0 ; for ( int i = 0 ; i <= Math . min ( N , K / B ) ; i ++ ) { if ( ( K - B * i ) % A == 0 ) { long j = ( K - B * i ) / A ; if ( j > N ) continue ; int jj = ( int ) j ; long c = fact [ i ] * factinv [ i ] % M ; c *= fact [ jj ] * factinv [ jj ] % M ; res += c % M ; res %= M ; } } return res ; }
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