Unhandled exception at 0xFFFFFFFF FFmpeg c++

I am testing code and I am getting error. What am I doing wrong?

Unhandled exception at 0xFFFFFFFF in ffmpeg.exe: 0xC0000005: Access violation executing location 0xFFFFFFFF.

# pragma comment (lib, "avformat.lib")

extern "C"
{
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
}

int main(int argc, char *argv[])
{
    AVFormatContext *pFormatContext = avformat_alloc_context();


}