How to allocate vector greater than 2Gb?

I need assistance on a C program i can't seem to figure out.

• prob2(): By using a pointer to pointer **A and the function calloc() allocate the memory for the 4x4 matrix A[][]. By using a pointer *b and the function malloc() allocate the memory for the 4-dimensional vector b[]. Read the components of A and b from the given input file matrix.dat. The last line of the input file contains the components of b. The rows of matrix A are the first four lines of the input file. Print the components of A[][] row by row, and the components of b[]. Using the function gauss() given in the lecture notes week9.txt, solve the system of linear algebraic equations A[][]*x[]=b[]. Print the components of the solution vector x[]. Calculate and print the length of this vector. Free the allocated memory.

• Answer:

  void prob2(void) { //printf("Put your solution for problem 2 here: "); char inputs[81]; int i, j, k, lines; double **A, *b, vec[4]; FILE *input; input = fopen("matrix.dat", "r"); while(fgets(inputs, 81, input) != NULL) { lines++; A = (double **)malloc(4*sizeof(double *)); for(i = lines; i