Compilare: main.c: In function 'run_combo': main.c:36:7: warning: unused variable 'i' [-Wunused-variable] i; ^ main.c: In function 'display': main.c:60:6: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen(FOUT, "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~ main.c: In function 'main': main.c:75:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen(FIN, "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~ main.c:77:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^~~~~~~~~~~~~~~ main.c:83:8: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v->data[i]); ^~~~~~~~~~~~~~~~~~~~~~~~