Compilare: user.cpp: In function ‘void antibfs(trie*)’: user.cpp:47:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0;j<fr->y.size();j++) sol[fr->y[j]]=fr->x; ^ user.cpp: In function ‘int main()’: user.cpp:51:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("seti.in","r",stdin); ^ user.cpp:52:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("seti.out","w",stdout); ^ user.cpp:53:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); gets(ss); ^ user.cpp:53:25: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); gets(ss); ^ user.cpp:55:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(ss+1); strcat(s+1,ss+1); ^ user.cpp:58:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); gets(ss); ^ user.cpp:58:25: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); gets(ss); ^ user.cpp:60:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(ss+1); add_intrie(i); ^ /tmp/ccEgdkht.o: In function `main': user.cpp:(.text.startup+0x6a): warning: the `gets' function is dangerous and should not be used.