Why does my Cs50 recover programme correctly recover all images except the first one?

Question

I wrote the below code and it recovers 51 images: 000.jpg to 050.jpg. All images except 000.jpg seems to have been found correctly. I'm not sure why the code isn't working?

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

//Define new data type BYTE
typedef uint8_t BYTE;

BYTE block[512];

int main(int argc, char *argv[])
{
    if (argc != 2)
    {
        printf("Usage: ./recover filename\n");
        return 1;
    }
    //initialise items
    int counterjpg = 0;
    FILE *img = NULL;
    char filename[8];

    //create buffer
    BYTE *buffer = malloc(512);

    //Open memory card
    FILE *memorycard = fopen(argv[1], "r");

    //Check if memory card does not open
    if (memorycard == NULL)
    {
        printf("Error: cannot open file\n");
        return 1;
    }

    //Repeat until end of card
    while (!feof(memorycard))
    {

        //Read 512 bytes into buffer
        fread(buffer, 512, 1, memorycard);

        //If start of new jpeg
        if (buffer[0] == 0xff && buffer[1] == 0xd8 && buffer[2] == 0xff && (buffer[3] & 0xf0) == 0xe0)
        {
            //If first jpeg
            if (counterjpg == 0)
            {
                sprintf(filename, "%03i.jpg", counterjpg);
                img = fopen(filename, "w");
                fwrite(buffer, 512, 1, img);
                counterjpg++;
            }

            //Else
            else
                //close current file
                fclose(img);

                //open new file
                sprintf(filename, "%03i.jpg", counterjpg);
                img = fopen(filename,"w");
                fwrite(buffer, 512, 1, img);
                counterjpg++;
        }
        //Else
        else
        {
            //If already found JPEG
            if (img != NULL)
            {
                //Keep writing to it
                fwrite(buffer, 512, 1, img);
            }
        }
    }
    free(buffer);
    fclose(memorycard);
    fclose(img);
    return 0;

}

Answer 1

You have 51 images can it be because 050.jpg is supposed to be 049.jpg and your 001.jpg is supposed to be your 000.jpg, check you initialization of your jpg counter

Answer 2

Worked it out - curly brackets around else statement were missing