Compilare: user.cpp: In function ‘TRIE* add(TRIE*, char*, int)’: user.cpp:39:19: warning: NULL used in arithmetic [-Wpointer-arith] if(word[0] == NULL) ^ user.cpp: In function ‘int main()’: user.cpp:104:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < srt.size(); i++) ^ user.cpp:114:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 1; (1<<j) <= tata.size(); j++) ^ user.cpp:88:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ratina.in","r",stdin); ^ user.cpp:89:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ratina.out","w",stdout); ^ user.cpp:94:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&nw,&nq); ^ user.cpp:98:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(cstr); ^ user.cpp:121:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&nw,&x); ^ user.cpp:124:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ /tmp/cc5UEupU.o: In function `main': user.cpp:(.text.startup+0x174): warning: the `gets' function is dangerous and should not be used.