Compilare: user.cpp: In function ‘void add(Node*, char*)’: user.cpp:22:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(node->v[c]==0){ ^ user.cpp:23:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] node->v[c]=new Node; ^ user.cpp:26:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] add(node->v[c],s+1); ^ user.cpp: In function ‘int del(Node*, char*)’: user.cpp:32:26: warning: array subscript has type ‘char’ [-Wchar-subscripts] else if(del(node->v[c],s+1)){ ^ user.cpp:33:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] node->v[c]=0; ^ user.cpp: In function ‘int que(Node*, char*)’: user.cpp:46:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(node->v[c]) ^ user.cpp:47:29: warning: array subscript has type ‘char’ [-Wchar-subscripts] return que(node->v[c],s+1); ^ user.cpp: In function ‘int pre(Node*, char*, int)’: user.cpp:52:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(*s=='\n'||node->v[c]==0) ^ user.cpp:54:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] return pre(node->v[c],s+1,k+1); ^ user.cpp: In function ‘int main()’: user.cpp:62:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(word,L+1,in); ^