Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:38:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[nod].size();i++) ^ user.cpp: In function ‘void Euler(int)’: user.cpp:72:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[nod].size();i++) ^ user.cpp: In function ‘void Plus_Minus(int)’: user.cpp:86:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[nod].size();i++) ^ user.cpp: In function ‘char nextch()’: user.cpp:15:29: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf,1,MAXBUF,fi); ^