void bellman_ford ( int v_num, int e_num, int source, int e[],
  double e_weight[], double v_weight[], int predecessor[] );
void i4mat_transpose_print ( int m, int n, int a[], string title );
void i4mat_transpose_print_some ( int m, int n, int a[], int ilo, int jlo,
  int ihi, int jhi, string title );
void i4vec_print ( int n, int a[], string title );
void r8vec_print ( int n, double a[], string title );
void timestamp ( );