Compilare: main.c: In function 'main': main.c:73:9: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen(FIN, "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~ main.c:75:9: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen(FOUT, "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:77:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^~~~~~~~~~~~~~~