Compilare: user.c: In function ‘main’: user.c:72:13: warning: array subscript has type ‘char’ [-Wchar-subscripts] fprintf(out, "%d %d %d %d %d %d\n", a[sum[i].ind1], ^ user.c:73:49: warning: array subscript has type ‘char’ [-Wchar-subscripts] a[sum[i].ind2], ^ user.c:74:49: warning: array subscript has type ‘char’ [-Wchar-subscripts] a[sum[i].ind3], ^ user.c:75:49: warning: array subscript has type ‘char’ [-Wchar-subscripts] a[sum[j].ind1], ^ user.c:76:49: warning: array subscript has type ‘char’ [-Wchar-subscripts] a[sum[j].ind2], ^ user.c:77:49: warning: array subscript has type ‘char’ [-Wchar-subscripts] a[sum[j].ind3]); ^ user.c:47:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d\n", &N, &S); ^ user.c:50:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &a[i]); ^