/* This is an example of the main program for project 2 phase 1. You can modity
	it, e.g. adding function calls to the function(s) you define in sparse.c.
   In this version, 
	command line safety check is done
        data structure (ROOT **M) is defined to store input
	void  read_input(FILE *F, ROOT *M, FILE *G) 
			// read in matrix from input file F, build a listed list
			// with ROOT M, and print out the memory location of F 
			// and M as well as the number of non-zero entries in M
			// on the screen and to the output file G 
	void show_list (ROOT *M, FILE *F)
			// print values in a listed list with ROOT M on the 
			// screen and to the output file F


   The p2.c that will be used to grade your project will be posted later. You 
	CANNOT make any changes to that file. 
								Gang Qu
								March 31, 2026
*/

#include <stdlib.h>
#include <stdio.h>
#include "sparse.h"			// include the header file


int main(int argc, char *argv[])
{ FILE *in, *out;
  ROOT **M; 
  int i, j, k;


  if (argc < 2)
  { printf("Usage: a.out input1 input2 ... output\n");
    exit(0);
  }

  M = (ROOT **) malloc((argc-1)*sizeof(ROOT *));
  if (M == NULL) 
    exit(0);

  out = fopen(argv[argc-1], "w");
  if (out == NULL)
  { printf("output file %s cannot open ...\n", argv[argc-1]);
    exit(0);
  }

  for (i=1; i<argc-1; i++)
  { in =  fopen(argv[i],  "r");
    if (in == NULL)
    { printf("Input %s not found ...\n", argv[i]);
      exit(0);
    }

    M[i-1] = make_root();
    read_input(in, M[i-1], out);
// printf("input %s:\n", argv[i]);		// no indent. Test only
    show_list(M[i-1], out);    
    fclose(in);
  }
  fclose(out);

  return 0;
}