Compilare: user.cpp: In function ‘int cmp(std::string, std::string)’: user.cpp:36:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(a.size()>m) return 1; ^ user.cpp:37:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(b.size()>m) return -1; ^ user.cpp: In function ‘void Schimba(int, int)’: user.cpp:44:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<way[x].size();i++) ^ user.cpp:49:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<way[y].size();i++) ^ user.cpp:54:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<aux.size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:61:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dir.in","r",stdin); ^ user.cpp:62:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dir.out","w",stdout); ^ user.cpp:63:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",s+1); ^