Compilare: user.cpp: In function ‘void BFS(int)’: user.cpp:22:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[cod[b]].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:57:11: warning: variable ‘n’ set but not used [-Wunused-but-set-variable] int i,n,m,x,y,a,b,d; ^ user.cpp: In function ‘char nextch()’: user.cpp:40:30: 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); ^