Why do we use define FILENAME "zone1.txt" but when we read it in with the while loop we only use zone? Why shouldn't it be while((fscanf(zone, "%lf %lf", &x, &y))==2) and what does ==2 mean is that the number of columns that should be read in?

#include #define FILENAME "zonel.txt" Fint main (void) { /* Declare and Initialize Variables*/ int count = 0; double x, y, first, last, sumx = 0, sumy = 0, sumx2 = 0, sumxy = 0, denom, m, b; FILE *zone ; /* Open Input File */ zone = fopen (FILENAME, "r"); if (zone==NULL) printf("Error opening input file. "); else /*While not at the end of the file */ /*read and accumulate information/ while( (fscanf (zone, " $16",&x, y)) == 2) ++ count