Compilare: main.cpp: In function 'void bfs()': main.cpp:30:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<d[x].size();i++){ ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:85:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("castel.in","r",stdin); ^ main.cpp:86:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("castel.out","w",stdout); ^ main.cpp:88:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&n,&m,&k); ^ main.cpp:93:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i][j]); ^