Scaling

#include "bits/stdc++.h"
#include "graphics.h"

using namespace std;

struct Matrix
{
      int row;
      int col;
      int mat[5][5];

      Matrix(int row = 0, int col = 0) : row(row), col(col)
      {
            for (int i = 0; i < row; i++)
            {
                  for (int j = 0; j < col; j++)
                  {
                        mat[i][j] = 0;
                  }
            }
      }
      Matrix multiply(const Matrix A, const Matrix B)
      {
            Matrix C;
            C.row = A.row;
            C.col = B.col;
            for (int i = 0; i < A.row; i++)
            {
                  for (int j = 0; j < B.col; j++)
                  {
                        int sum = 0;
                        for (int k = 0; k < A.col; k++)
                        {
                              sum += A.mat[i][k] * B.mat[k][j];
                        }
                        C.mat[i][j] = sum;
                  }
            }
            return C;
      }
};

struct Point
{
      int x;
      int y;
      Point(int x = 0, int y = 0)
            : x(x)
            , y(y) {}
};

void scale(vector <Point> &points, Point scaleFactor)
{
      // Triangle Before Scaling
      setcolor(RED);
      line(points[0].x, points[0].y, points[1].x, points[1].y);
      line(points[1].x, points[1].y, points[2].x, points[2].y);
      line(points[0].x, points[0].y, points[2].x, points[2].y);

      // Initializing scaling matrix
      Matrix scalingMatrix(2, 2);
      scalingMatrix.mat[0][0] = scaleFactor.x;
      scalingMatrix.mat[1][1] = scaleFactor.y;

      // Scaling the triangle
      for (Point &p : points)
      {
            Matrix pointToMatrix = Matrix(2, 1);
            pointToMatrix.mat[0][0] = p.x;
            pointToMatrix.mat[1][0] = p.y;
            Matrix mul = pointToMatrix.multiply(scalingMatrix, pointToMatrix);
            p.x = mul.mat[0][0];
            p.y = mul.mat[1][0];
      }

      // Triangle after Scaling
      setcolor(GREEN);
      line(points[0].x, points[0].y, points[1].x, points[1].y);
      line(points[1].x, points[1].y, points[2].x, points[2].y);
      line(points[0].x, points[0].y, points[2].x, points[2].y);
}

signed main()
{
      freopen("scale_in.txt", "r", stdin);

      vector <Point> points(3);
      for (Point &p : points) cin >> p.x >> p.y;
      Point scaleFactor;
      cin >> scaleFactor.x >> scaleFactor.y;

      int gd = DETECT;
      int gm;
      detectgraph(&gd, &gm);
      initgraph(&gd, &gm, "");
      scale(points, scaleFactor);
      getch();
      closegraph();
}