Compilare: user.cpp: In function ‘void add(int)’: user.cpp:27:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<c.size();i++) ^ user.cpp: In function ‘void bfs()’: user.cpp:41:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0;k<C.size();k++) ^ user.cpp: In function ‘int main()’: user.cpp:70:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.in","r",stdin); ^ user.cpp:71:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ahocorasick.out","w",stdout); ^