class Num {
 public:
  Num(int value, int modulo);

  Num &operator=(const Num &other);

  Num operator+(const Num &other);
  Num operator-(const Num &other);
  Num operator*(const Num &other);
  Num operator+(int num);
  Num operator-(int num);
  Num operator*(int num);

  Num &operator+=(const Num &other);
  Num &operator-=(const Num &other);
  Num &operator*=(const Num &other);
  Num &operator+=(int num);
  Num &operator-=(int num);
  Num &operator*=(int num);

  int value;
  int modulo;
};

#include <algorithm>
Num::Num(int value, int modulo) : value(value), modulo(modulo) {
  if (this->modulo != 0)
	this->value %= this->modulo;
}

Num &Num::operator=(const Num &other) {

  Num tmp = other;
  // the are much better way is create member f that is wrapper calling copy & swap
  // but now we doing shit
  std::swap(this->modulo, tmp.modulo);
  std::swap(this->value, tmp.value);
  return *this;
}

Num Num::operator+(const Num &other) {
  Num obj = *this;
  return obj += other;
}

Num Num::operator-(const Num &other) {
  Num obj = *this;
  return obj -= other;
}

Num Num::operator*(const Num &other) {
  Num obj = *this;
  return obj *= other;
}

Num Num::operator+(int num) {
  Num obj = *this;
  return obj += num;
}

Num Num::operator-(int num) {
  Num obj = *this;
  return obj -= num;
}

Num Num::operator*(int num) {
  Num obj = *this;
  return obj *= num;
}

Num &Num::operator+=(const Num &other) {
  int64_t buf = this->value;
  buf += other.value;
  buf %= modulo;
  this->value = buf;
  return *this;
}

Num &Num::operator-=(const Num &other) {
  int num = ( this->value - other.value ) % this->modulo;   // 4 - 12
  if (num < 0)
	num = ( this->modulo + num ) % this->modulo;
  this->value = num;
  return *this;
}

Num &Num::operator*=(const Num &other) {
  int64_t buf = this->value;
  buf *= other.value;
  buf %= modulo;
  this->value = buf;
  return *this;
}

Num &Num::operator+=(int num) {
  *this += Num(num, 0);
  return *this;
}

Num &Num::operator-=(int num) {
  *this -= Num(num, 0); //hm
  return *this;
}

Num &Num::operator*=(int num) {
  return *this *= Num(num, 0);
}