Compilare: main.cpp: In function 'void bfs(int)': main.cpp:20:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<gr[x].size();i++){ ~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:32:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&n,&m); ^ main.cpp:35:29: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d%d",&x,&y); ^