10451 : 순열 사이클 (DFS) [C++]

#include <iostream>
#include <vector>

using namespace std;

class Cycle
{
private:
 vector<int> Relation;
 int Count = 0;
public:
 Cycle(int n);
 void DFS(int target, int destination);
 int GetNumber(int index);
 void Print();
};

Cycle::Cycle(int n)
{
 for (int i = 0; i < n; i++)
 {
  int Temp;
  cin >> Temp;
  this->Relation.push_back(Temp);
 }
}

void Cycle::DFS(int target, int destination)
{
 if (target < 0)
  return;

 int t_temp = this->Relation[target] - 1;

 this->Relation[target] = -1;

 if (t_temp == destination)
  this->Count += 1;
 else
  DFS(t_temp, destination);
}

int Cycle::GetNumber(int index)
{
 return this->Relation[index];
}

void Cycle::Print()
{
 cout << this->Count << endl;
}

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

 while (iTestCase--)
 {
  int N;
  cin >> N;

  Cycle C(N);
  
  for (int j = 0; j < N; j++)
   C.DFS(C.GetNumber(j) - 1, j);

  C.Print();
 }
}