Anticlockwise spiral view of diamond matrix elements in c++

C++ program for Anticlockwise spiral view of diamond matrix elements. Here more solutions.

// Include header file
#include <iostream>
#include <vector>
using namespace std;
/*
  C++ program for
  Anticlockwise spiral view of diamond element in matrix
*/
class SpiralTraversal
{
	public:
		// Method which is displaying the Anticlockwise spiral 
		// Of matrix in diamond(mid) element
		void spiralView(vector < vector < int >> matrix, 
                        int x, int y, int p, int q, int k)
		{
			// Find the middle column
			int mid_col = y + ((q - y) / 2);
			// Get middle row (valid for odd square matrix)
			int mid_row = mid_col;
			// Matrix are divided into 4 section
			// Starting of middle row and column in form of top
			// Case A
			// Top to Left-bottom
			int i = mid_col;
			int j = 0;
			while (i > y && k > 0)
			{
				cout << "  " << matrix[x + j][i];
				i--;
				k--;
				j++;
			}
			// Case B
			// Middle left to middle right bottom
			i = y;
			j = 0;
			while (i <= mid_col && k > 0)
			{
				cout << "  " << matrix[(mid_row) + j][i];
				i++;
				k--;
				j++;
			}
			// Case C
			// Middle bottom to middle right side 
			i = mid_col + 1;
			j = 1;
			while (i <= q && k > 0)
			{
				cout << "  " << matrix[(p) - j][i];
				i++;
				k--;
				j++;
			}
			// Case D
			// Middle right side to  top middle 
			i = q - 1;
			j = 1;
			while (i > mid_col && k > 0)
			{
				cout << "  " << matrix[(mid_row) - j][i];
				i--;
				k--;
				j++;
			}
			if (x + 1 <= p - 1 && k > 0)
			{
				// Recursive call
				this->spiralView(matrix, x + 1, y + 1, p - 1, q - 1, k);
			}
		}
	void diamondAnticlockwise(vector < vector < int >> matrix)
	{
		int row = matrix.size();
		int col = matrix[0].size();
		// Check whether the given matrix is a valid odd shape or not
		if (row != col || col % 2 == 0)
		{
			// When Yes not a valid size
			cout << "\nNot a valid perfect Odd square matrix" << endl;
			return;
		}
		// (row*col)-((col+1)/2)*4 are provide the value of number of 
		// Diamond element
		this->spiralView(matrix, 0, 0, row - 1, 
             col - 1, (row *col) - ((col + 1) / 2) *4);
	}
};
int main()
{
	SpiralTraversal *task = new SpiralTraversal();
	// Define matrix 
	vector < vector < int >> matrix {
      {1,  2,  3,  4,  5},
      {6,  7,  8,  9,  10},
      {11, 12, -1, 15,  16},
      {17, 18, 19, 20,  21},
      {22, 23, 24, 25,  26}
    }; 
	task->diamondAnticlockwise(matrix);
	return 0;
}

Output

  3  7  11  18  24  20  16  9  8  12  19  15  -1