Compilare: user.cpp: In function ‘void AddLetter(int)’: user.cpp:33:30: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(tree[node].next[letter]!=0){ ^ user.cpp:34:38: warning: array subscript has type ‘char’ [-Wchar-subscripts] suffix=tree[node].next[letter]; ^ user.cpp:41:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] tree[node].next[letter]=nodes; ^ user.cpp:51:52: warning: array subscript has type ‘char’ [-Wchar-subscripts] tree[nodes].fail=tree[node].next[letter]; ^ user.cpp: In function ‘int main()’: user.cpp:64:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pal2.in","r",stdin); ^ user.cpp:65:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pal2.out","w",stdout); ^ user.cpp:68:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",s); ^