Compilare: user.cpp: In function ‘int bfs()’: user.cpp:22:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<L[a].size();i++){ ^ user.cpp: In function ‘void sfb()’: user.cpp:43:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<L[a].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:66:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<L[n].size();i++){ ^ user.cpp:57:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&m); ^ user.cpp:59:46: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&z[i].a,&z[i].b,&a); ^