Simulate mouse move and click

Just for fun. These code moves the mouse and click on the left button:

#define WIN32_LEAN_AND_MEAN

#include <Windows.h>


void LeftClick( )
{  
    INPUT input = { 0 };
    input.type = INPUT_MOUSE;
    input.mi.dwFlags = MOUSEEVENTF_LEFTDOWN;
    ::SendInput(1, &input, sizeof(INPUT));

    ::ZeroMemory(&input, sizeof(INPUT));
    input.type = INPUT_MOUSE;
    input.mi.dwFlags = MOUSEEVENTF_LEFTUP;
    ::SendInput(1, &input, sizeof(INPUT));
}

void MouseMove (int x, int y )
{  
    double fScreenWidth = ::GetSystemMetrics(SM_CXSCREEN) - 1; 
    double fScreenHeight  = ::GetSystemMetrics(SM_CYSCREEN) - 1; 
    double fx = x * (65535.0f / fScreenWidth);
    double fy = y * (65535.0f / fScreenHeight);
    INPUT  input = { 0 };
    input.type = INPUT_MOUSE;
    input.mi.dwFlags = MOUSEEVENTF_MOVE | MOUSEEVENTF_ABSOLUTE;
    input.mi.dx = fx;
    input.mi.dy = fy;
    ::SendInput(1, &input, sizeof(INPUT));
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, 
                   LPSTR lpCmdLine, int nShowCmd)
{
    MouseMove(500, 500);
    LeftClick();
    return 0;
}