Compilare: user.cpp: In function ‘void addHash(std::pair<int, int>)’: user.cpp:26:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<Hash[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:75:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<words[i].size();j++) ^ user.cpp:67:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(S, sizeof(S), f); ^