Compilare: user.cpp: In function ‘int main()’: user.cpp:55:47: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(i<n && s && rang[sign[a[i]]-MAX]<=rang[S[s]-MAX] && S[s]!=sign['(']) ^ user.cpp:59:31: warning: array subscript has type ‘char’ [-Wchar-subscripts] S[++s]=sign[a[i]]; ^ user.cpp:64:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<post.size();++i) ^ user.cpp:22:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("evaluare.in","r",stdin); ^ user.cpp:23:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("evaluare.out","w",stdout); ^ user.cpp:25:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a+1); ^ /tmp/ccWNoryS.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.