automated mouse clicks make screen go blank

I am working on writing a program that will do a few mouse clicks for me in a loop. I created a struct and set it to type INPUT_MOUSE to replicate the clicks and used SendInput() to send the info. everything compiles right and could be called a "working" program but I ran into a rather funny glitch. I wrote the program on my laptop (windows vista) tried it and it worked fine. When I rewrote the same exact code and used it on my desktop (Windows 7) when I run the program my screen will go to black as soon as I start the automation part of the program just like it does when it goes into sleep mode. The program will run in the background just fine, but its kind of a pain that the automater blacks my screen out. What is going on here?

I am adding my code:

        #include "stdafx.h"

        #include <windows.h>
        #include <iostream>
        #include <string>
        #include <time.h>

        using namespace std;





        void clicky(int x, int y)
        {
            // 5 sec wait
                clock_t run;
                run = clock()+5*CLOCKS_PER_SEC;
                while (clock() < run) {}


            //plug in cursor coords and click down and up
                SetCursorPos(x,y);

                INPUT mouse;
                mouse.type = INPUT_MOUSE;
                mouse.mi.dwFlags = MOUSEEVENTF_LEFTDOWN;
                SendInput(1,&mouse,sizeof(INPUT));

                mouse.type = INPUT_MOUSE;
                mouse.mi.dwFlags= MOUSEEVENTF_LEFTUP;
                SendInput(1,&mouse,sizeof(INPUT));
     



    



        }


        void main()


        {
   开发者_StackOverflow         int coords=0;
            string h;
            //find out how many clicks are needed
            cout << "How many clicks will you need?";
            cin >> coords;
            //extra getline here without it when return is hit
            //from entering the click amount it would also enter
            //a cursor coordinate
            getline(cin,h);


            POINT p[21];
            for (int count = 1;count<=coords;count++)
            {
                cout << "Place mouse cursor where you want a click and press return"<<endl;
                //each time return is hit the cursor coordinates
                //will be stored in the corresponding spot in 
                // the p array
                    string key = "r";
                    getline(cin,key);
                    GetCursorPos(&p[count]);
                    break;
    

    
    
            }

            string go;
            cout << "Hit Return to initialize your click loop";
            getline(cin,go);

            while (true)
            //infinite loop cycling through the users
            //cursor coordinates and clicking
            {
                for(int click=1;click<=coords;click++)
                {
                    int x = p[click].x;
                    int y = p[click].y;
                    clicky(x,y);
                }

            }

        }

Try initializing the INPUT structure to all zeroes before calling SendInput(), like

INPUT i;
ZeroMemory(&i, sizeof(i));

In addition to that, make sure that the coordinates you specify are not too large.

I had the screen go blank (in fact, the screensaver kicked in) when doing either of these two wrong.