Compilare: user.cpp: In function ‘int main()’: user.cpp:116:32: warning: format ‘%s’ expects argument of type ‘char*’, but argument 3 has type ‘char (*)[30]’ [-Wformat=] scanf("%d %s",&type,&ch); ^ user.cpp:111:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.in","r",stdin); ^ user.cpp:112:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.out","w",stdout); ^ user.cpp:116:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %s",&type,&ch); ^