Compilare: user.cpp: In function ‘int main()’: user.cpp:35:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(tm->po[in[j]]==NULL) ^ user.cpp:36:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] tm->po[in[j]]=new nod(); ^ user.cpp:37:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] tm=tm->po[in[j]]; ^ user.cpp:48:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(tm->po[si[j]]!=NULL) ^ user.cpp:50:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] tm=tm->po[si[j]]; ^ user.cpp:20:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("enigma.in","r",stdin); ^ user.cpp:21:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("enigma.out","w",stdout); ^ user.cpp:25:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&n,&m); ^ user.cpp:26:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(si+1); ^ user.cpp:29:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(in+1); ^ /tmp/cct4Aj4R.o: In function `main': user.cpp:(.text.startup+0x9c): warning: the `gets' function is dangerous and should not be used.