Compilare: user.c: In function ‘main’: user.c:28:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.in", "r", stdin); ^ user.c:29:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.out", "w", stdout); ^ user.c:31:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s%s", a + 1, b + 1); ^