Compilare: user.cpp: In function ‘bool bellmanford()’: user.cpp:37:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vecin[nod].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:52:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("bellmanford.in","r",stdin); ^ user.cpp:53:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("bellmanford.out","w",stdout); ^ user.cpp:56:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&n,&m); ^ user.cpp:59:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d",&x,&y,&z); ^