Compilare: main.cpp: In function 'int main()': main.cpp:20:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.in","r",stdin); ^ main.cpp:21:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.out","w",stdout); ^ main.cpp:22:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &s); ^ main.cpp:24:53: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &nr1, &nr2),graf[nr1].push_back(nr2); ^