Compilare: user.cpp: In function ‘int bfs()’: user.cpp:16:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<L[a].size(); i++){ ^ user.cpp: In function ‘int main()’: user.cpp:39:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<L[n].size(); i++){ ^ user.cpp:31:24: 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:33:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&a,&b,&C); ^