Opencv image clipping split screen display example

Using OPENCV image processing library, the image clipping split screen display

//#include "stdafx.h"
#include <opencv2/opencv.hpp>

//#include <opencv2/imgproc/imgproc.hpp>
//#include <opencv2/highgui/highgui.hpp>
#include <iostream>
#include <vector>
using namespace std;
using namespace cv;

//The cut picture is m * n pieces
void Cut_img(Mat src_img,int m,int n,Vector<Mat> ceil_img)
{
 int t = m * n;
 int height = src_img.rows;
 int width  = src_img.cols;
 int ceil_height = height/m;
 int ceil_width  = width/n; 
 Mat roi_img,tmp_img;
 Point p1,p2;
 for(int i = 0;i<m;i++)
  for(int j = 0;j<n;j++){
   //p1 = 
   Rect rect(i+j*ceil_width,j+i*ceil_height,ceil_width,ceil_height);
   src_img(rect).copyTo(roi_img);
   ceil_img.push_back(roi_img);
   imshow("roi_img",roi_img);
   //rectangle(i+j*ceil_width,j+i*ceil_height,);
  } 
 waitKey(0);
}
void show_images(Vector<Mat> imgs,int n){

     //do something
}
int main()
{
 Mat img = imread("airplane.jpg",1);
 imshow("src img",img);
 int m = 3;
 int n = 3;
 Vector<Mat> ceil_img = m*n;
 Cut_img(img,m,n,ceil_img);
 waitKey();
 return 0;
}
 Compile command:  g++ -ggdb `pkg-config --cflags opencv` -o ImageTake ImageTake.cpp `pkg-config --libs opencv`;