Compilare: user.cpp: In function ‘int main()’: user.cpp:63:15: warning: variable ‘b’ set but not used [-Wunused-but-set-variable] trie *a, *b; ^ user.cpp:67:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d ", &n); ^ user.cpp:125:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d ", &n); ^