C - read and store data file for further calculations

Question

I normally use R, and have a lot of trouble understanding C. I need to read and store a data file, shown below, so that I can perform calculations on the data.

Answer 1

An example for writing:

FILE *fp;
fp=fopen("c:\\test.bin", "wb");
char x[10]="ABCDEFGHIJ";
fwrite(x, sizeof(x[0]), sizeof(x)/sizeof(x[0]), fp);

(write declaration)

size_t fwrite(const void *ptr, size_t size_of_elements, size_t number_of_elements, FILE *a_file);

If you were to read,

size_t fread(void *ptr, size_t size_of_elements, size_t number_of_elements, FILE *a_file);