OpenCV error

[dNocito]

I'm starting to use OpenCV and I'm doing the introduction tutorial but I keep getting this error message fatal error: opencv2/core/core.hpp: No such file or directory. I have included the header file. I'm using codeblocks. Do I some how need to tell it to use the libraries of OpenCV. I wasn't prompted to do so when I downloaded OpenCV

  #include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>

using namespace cv;
using namespace std;

int main( int argc, char** argv )
{
    if( argc != 2)
    {
     cout <<" Usage: display_image ImageToLoadAndDisplay" << endl;
     return -1;
    }

    Mat image;
    image = imread(argv[1], CV_LOAD_IMAGE_COLOR);   // Read the file

    if(! image.data )                              // Check for invalid input
    {
        cout <<  "Could not open or find the image" << std::endl ;
        return -1;
    }

    namedWindow( "Display window", WINDOW_AUTOSIZE );// Create a window for display.
    imshow( "Display window", image );                   // Show our image inside it.

    waitKey(0);                                          // Wait for a keystroke in the window
    return 0;
}


/// here is the header


#ifndef CORE_HPP_INCLUDED
#define CORE_HPP_INCLUDED



#endif // CORE_HPP_INCLUDED

[dNocito]

I found my answer at http://kevinhughes.ca/tutorials/opencv-install-on-windows-with-codeblocks-and-mingw/