Compilare: main.c:17:1: warning: data definition has no type or storage class fgetc(fp); ^~~~~ main.c:17:1: warning: type defaults to 'int' in declaration of 'fgetc' [-Wimplicit-int] main.c:17:1: warning: parameter names (without types) in function declaration main.c: In function 'main': main.c:153:11: warning: unused variable 'fp' [-Wunused-variable] FILE *fp = fopen("da.out", "w"); ^~ main.c: In function 'read': main.c:21:5: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(fp,"%d%d%d%d%d%d", &n,&m,&si, &sj, &fi, &fj); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~