adding two images

#include <opencv2/core/core.hpp>#include <opencv2/imgproc/imgproc.hpp>#include <opencv2/highgui/highgui.hpp>#include <iostream>#include <sstream>using namespace std;using namespace cv;/*************************************************************************  blending two images with the same size                                                              /************************************************************************/                                                                  int main(int argc, char* argv[]) {  double alpha = 0.5;double beta;double input;// Ask the user enter alphacout << " Simple Linear Blender " << endl;cout << "-----------------------" << endl;cout << "* Enter alpha [0-1]: ";cin  >> input;if (input > 0.0 && input < 1.0) {alpha = input;beta = 1 - alpha; }Mat image1 = imread("marais.jpg");Mat image2 = imread("dog.jpg");Mat result;if (image1.data && image2.data) {if (image1.size() == image2.size()) {addWeighted(image1, alpha, image2, beta, 0.0, result);}else {cout << " the size of the two images is not the same!" << endl;return -1;}}else {cout << "the error of loading images!" << endl;return -1;}imshow("Blending image", result);waitKey(0);return 0;}