Compilare: user.c: In function ‘main’: user.c:17:10: warning: variable ‘ch’ set but not used [-Wunused-but-set-variable] char ch; ^ user.c:21:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d ", &n, &m); ^ user.c: In function ‘getch’: user.c:10:14: warning: ignoring return value of ‘fread’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, BUF_SIZE, fin); ^