Thread: From a file into an array.

I am trying to read the first value of a file, allocate an array of the amount equal to the first value, then read the rest (the number of places already defined) of the file into that array. I have already done something similar using file pointers:

Code:

int main(int argc, char *argv[])
{

	int numberOfChar;
        int thisInt;
	int currentInt;



   	FILE *fp;
	fp=fopen("test.txt", "rb");
	if (fscanf(fp, "%d", &numberOfChar) == 1)
	printf("%d\n", numberOfChar);
	


for(currentInt = 0; currentInt < numberOfChar; currentInt++)
	{
	fscanf(fp, "%d", &thisInt);
	printf("%d\n", thisInt);
	
}

	printf("\n");
	printf("\n");
	

 return 0;
}

But I'm trying to do it with arrays now, so as to manipulate the array afterward. I can read the first int of the file and allocate the array:

Code:

    int numberOfChar;

   	FILE *fp;
	fp=fopen("test.txt", "rb");
	if (fscanf(fp, "%d", &numberOfChar) == 1)
	
	int x[numberOfChar]; //making array x have a size of numberOfChar

But reading the rest of the file, only to the numberOfChar, I can't figure out. I have seen arrays being made in C++ from user input:

Code:

int s;

	for (s = 0; s < numberOfChar; s++)
   	{
   	cout << "Enter an integer: ";
   	cin >> A[s];
   	}

	for (s = 0; s < numberOfChar; s++)
   	cout << A[s] << endl;

But I am trying to do it from a file, in C. I believe it will be a similar for loop though. I believe I have it allocated right, but how do I keep writing data into the array? Thank you in advance!