6064 : 카잉 달력 [C++]

#include <iostream>

using namespace std;

class KaIn
{
private:
 int M, N, x, y;
public:
 KaIn(int _m, int _n, int _x, int _y);
 int GetCount();
};

KaIn::KaIn(int _m, int _n, int _x, int _y)
{
 if (_m < _n)
 {
  this->M = _m; this->N = _n; this->x = _x; this->y = _y;
 }
 else
 {
  this->M = _n; this->N = _m; this->x = _y; this->y = _x;
 }
}

int KaIn::GetCount()
{
 int _X = 1; int _Y = 1;
 bool IsOk = false;
 int Count = 1;

 while (true)
 {
  if (_X < this->M && _Y < this->N)
  {
   _X++; _Y++;
   Count++;
  }
  else if (_X == this->M && _Y < this->N)
  {
   _X = 1; _Y++;
   Count++;
  }
  else if (_X < this->M && _Y == this->N)
  {
   _X++; _Y = 1;
   Count++;
  }
  else if (_X == this->M && _Y == this->N)
  {
   _X = 1; _Y = 1;
   Count++;
  }
  if (_X == this->x && _Y == this->y)
  {
   IsOk = true;
   break;
  }
  if (_X == this->M && _Y == this->N)
   break;
 }

 if (this->x == this->M && this->y == this->N)
  return Count;
 else if (!IsOk)
  return -1;
 else
  return Count;
}

int main()
{
 int testcase;
 cin >> testcase;

 while (testcase--)
 {
  int M, N, x, y;
  cin >> M >> N >> x >> y;

  KaIn Calendar(M, N, x, y);

  int Count = Calendar.GetCount();

  cout << Count << endl;
 }
}