Compilare: user.c: In function ‘factor’: user.c:23:11: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(semn==-1) ^ user.c:38:7: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(semn==-1) ^ user.c: In function ‘main’: user.c:99:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("logic.in","r",stdin); ^ user.c:100:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("logic.out","w",stdout); ^ user.c:101:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^