Error when initialize NTL vector in a class

Question

In my code, I've used many NTL vector and matrix as class members. Most of the variables can initialize as a zero-length vector or matrix. But the last one (randE), it somehow defaults to a vector with size=4444736032 and fixed.

class MyClass
{
public:
  shared_ptr<OtherClass> ptr;

  Mat<ZZ_p> A;
  Mat<ZZ_p> B;
  Mat<ZZ_p> C;
  Vec<ZZ_p> D;    
  Vec<ZZ_p> randA;
  Vec<ZZ_p> randB;
  Vec<ZZ_p> randC;
  ZZ_p randD;    
  Mat<ZZ_p> E;
  Vec<ZZ_p> randE;

  MyClass(
      const shared_ptr<OtherClass> &ptr;
      const Mat<ZZ_p> &A,
      const Mat<ZZ_p> &B,
      const Mat<ZZ_p> &C)
  {
    this->ptr = ptr;
    this->A = A;
    this->B = B;
    this->C = C;
  }
}

I've tried to add initialization inside the constructor, it'll throw an error, due to the vector is fixed, it cannot change its length.

// Error: SetLength: can't change this vector's length
this->randE = Vec<ZZ_p>();