Compilare: user.cpp: In function ‘int bfs()’: user.cpp:25:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); ++i) ^ user.cpp:42:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:46:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.in","r",stdin); ^ user.cpp:47:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.out","w",stdout); ^ user.cpp:50:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &x); ^ user.cpp:53:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ user.cpp:60:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a); ^