Compilare: user.cpp: In function ‘bool dijekstra()’: user.cpp:46:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<V[now.nod].size();i++) ^ user.cpp: In function ‘void Belman_ford()’: user.cpp:99:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<V[now.nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:118:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in","r",stdin); ^ user.cpp:119:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out","w",stdout); ^ user.cpp:120:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&s,&d); ^ user.cpp:124:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x,&y,&flow,&cost); ^