Compilare: user.cpp: In function ‘void ins(Trie*, char*)’: user.cpp:28:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(nod->fiu[CH[*s]]==NULL) ^ user.cpp:29:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] nod->fiu[CH[*s]]=new Trie; ^ user.cpp:30:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] ins(nod->fiu[CH[*s]],s+1); ^ user.cpp: In function ‘int main()’: user.cpp:74:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d %d %d\n",&N,&K,&W,&D); ^ user.cpp:77:25: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(c+1,LEN,f); ^ In file included from /usr/include/stdio.h:934:0, from /usr/include/c++/4.8/cstdio:42, from user.cpp:1: In function ‘char* fgets(char*, int, FILE*)’, inlined from ‘int main()’ at user.cpp:77:25: /usr/include/i386-linux-gnu/bits/stdio2.h:253:58: warning: call to ‘__fgets_chk_warn’ declared with attribute warning: fgets called with bigger size than length of destination buffer [enabled by default] return __fgets_chk_warn (__s, __bos (__s), __n, __stream); ^