Getting garbage value at the end of some strings - c

Question

I scraped a website to get some mcqs for a c assignment. I wrote the data to a plaintext file separating every entry with null chars.
The pattern is:
Question with choices NULL Answer NULL Question...
Here is a sample of the file. the red dots are '\0' chars:
Here is a link to get the full file.
Code to read this file in C:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Question{
char question[1000];
char answer;
};
int main(){
struct Question questions[100];
FILE *fp;
char buffer[1000],choice;
int ch,i=0,c=1,k=0,score=0;
fp=fopen("quiz_questions.txt","r");
ch = 1;
while (ch != EOF)
{
ch = getc(fp);
buffer[i]=ch;
i++;
if(ch=='\0'){
buffer[i]='\0';
c++;
i=0;
continue;
}
if(c%2){ //question
strcpy(questions[k].question,buffer);
}
else{ //answer
questions[k].answer=buffer[0];
k++;
}
}
for(i=0;i<35;i++){
printf("\nQuestion:\n%s\nAnswer: %c\n",questions[i].question,questions[i].answer);
}
return 0;
}
OUTPUT:
What am I missing? Help please. It seems the buffer isn't getting null terminated properly and is retaining chars from last assignment.
PS: Is there a better way to consume this data from c? Scraping done via python.
EDIT: I now realize writing a separate answerkey file would have been much better. Stupid me.

Answer 1

strcpy(questions[k].question,buffer);
This statement is executed for every single character you read (if c is odd). At this point, buffer is not null terminated yet (and not a string).
ch = getc(fp);
buffer[i]=ch;
These two lines write to buffer[i] even if the end of file was reached. You only check for EOF after having processed it as if it were a normal character.
i++;
if(ch=='\0'){
buffer[i]='\0';
This is redundant. If ch is '\0', then you've just null terminated buffer in buffer[i]=ch;. There's no need to add another '\0'.

Answer 2

Modified version of your code to solve the problem:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Question{
char question[1000];
char answer;
};
int main()
{
struct Question questions[100];
FILE *fp;
char buffer[1000],choice;
int ch,i=0,c=0,k=0,score=0; **<-- EDIT:change done here to initialize c = 0**
fp=fopen("quiz_questions.txt","r");
ch = 1;
while (ch != EOF)
{
ch = getc(fp);
buffer[i]=ch;
i++;
if(ch =='\0')
{
//buffer[i]='\0'; <-- Change done here, unnecessary assignment
c++;
i=0;
if(c%2) <-- Change done here, moved inside if (ch == '\0') case
{
//question
strcpy(questions[k].question,buffer);
}
else
{
//answer
questions[k].answer=buffer[0];
k++;
}
}
}
for(i=0;i<35;i++)
{
printf("\nQuestion:\n%s\nAnswer: %c\n",questions[i].question,questions[i].answer);
}
return 0;
}