Compilare: user.cpp: In function ‘int bfs(int)’: user.cpp:36:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<l[k].size();i++) ^ user.cpp:55:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘void read()’: user.cpp:15:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d%d",&n,&m,&s,&fin); ^ user.cpp:18:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d%d%d",&x,&y,&k); ^