#pragma GCC optimize ( "O3" ) #pragma GCC optimize( "unroll-loops" ) #pragma GCC target ( "sse4.2,fma,avx2,popcnt,lzcnt,bmi2" ) #include #include #include #include #include using namespace std; #define MAIN main #define TYPE_OF( VAR ) remove_const::type >::type #define UNTIE ios_base::sync_with_stdio( false ); cin.tie( nullptr ) #define CEXPR( LL , BOUND , VALUE ) constexpr const LL BOUND = VALUE #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 QUIT return 0 #define COUT( ANSWER ) cout << ( ANSWER ) << "\n" #define RETURN( ANSWER ) COUT( ANSWER ); QUIT template inline T Residue( const T& a , const T& p ){ return a >= 0 ? a % p : ( a % p ) + p; } #define POWER_MOD( ANSWER , ARGUMENT , EXPONENT , MODULO ) \ int ANSWER{ 1 }; \ { \ int ARGUMENT_FOR_SQUARE_FOR_POWER = ( MODULO + ( ( ARGUMENT ) % MODULO ) ) % MODULO; \ TYPE_OF( EXPONENT ) EXPONENT_FOR_SQUARE_FOR_POWER = ( EXPONENT ); \ while( EXPONENT_FOR_SQUARE_FOR_POWER != 0 ){ \ if( EXPONENT_FOR_SQUARE_FOR_POWER % 2 == 1 ){ \ ANSWER = ( ANSWER * ARGUMENT_FOR_SQUARE_FOR_POWER ) % MODULO; \ } \ ARGUMENT_FOR_SQUARE_FOR_POWER = ( ARGUMENT_FOR_SQUARE_FOR_POWER * ARGUMENT_FOR_SQUARE_FOR_POWER ) % MODULO; \ EXPONENT_FOR_SQUARE_FOR_POWER /= 2; \ } \ } \ #define CONVERT1( i , P ) \ int P ## 00 = i / d; \ coprime = true; \ FOR( n , 0 , num ){ \ if( P ## 00 % prime[n] == 0 ){ \ coprime = false; \ break; \ } \ } \ #define CONVERT2( i , P ) \ int P ## 01 = i % d; \ int MAIN() { UNTIE; CEXPR( int , bound_B , 600 ); CIN_ASSERT( B , 1 , bound_B ); CIN( int , C ); assert( 1 <= C && B % C == 0 ); int B_copy = B; int prime[4]; int euler = 1; int num = 0; FOR( i , 2 , B_copy ){ if( i * i > B_copy ){ break; } if( B_copy % i == 0 ){ prime[num++] = i; B_copy /= i; euler *= i - 1; while( B_copy % i == 0 ){ B_copy /= i; euler *= i; } } } if( B_copy > 1 ){ prime[num++] = B_copy; euler *= B_copy - 1; } int inv[bound_B]; FOR( i , 1 , B ){ POWER_MOD( i_inv , i , euler - 1 , B ); inv[i] = i_inv; } CEXPR( int , bound_Bd , bound_B * bound_B ); bool found[bound_Bd] = {}; int d = B / C; int Bd = B * d; int answer = 0; bool coprime; CEXPR( int , bound_answer , 100 ); FOR( i , 0 , Bd ){ if( found[i] ){ continue; } CONVERT1( i , P ); if( !coprime ){ continue; } answer++; if( answer > bound_answer ){ cout << bound_answer; RETURN( "+" ); } CONVERT2( i , P ); FOR( j , 0 , Bd ){ CONVERT1( j , R ); if( !coprime ){ continue; } CONVERT2( j , R ); int& detR_inv = inv[R00]; found[ detR_inv * P00 * R00 % B * d + detR_inv * ( ( P00 - 1 ) * R01 + P01 ) % d ] = true; } } RETURN( answer ); }