Dereferenced pointer returning junk

Question

Sorry in advance as I am a novice. I'm struggling with pointers in general, and this case is no different. When I call my getter that's supposed to output elements of an array, I get a random long integer that changes every time I run the program. I know the code is all over the place. I took out as much as possible to keep it short, but let me know if more is needed.

Class Class1 {

public:

const static int SIZE = 4;

// Actual project is split .h and .cpp

Class1() {
  for (int i = 0; i < SIZE; ++i) {
    numThings[i] = 0;
  }
}
Class1(int* thingsPtr) {
  SetNumThings(thingsPtr);
}

void SetNumThings(int numThings[]) {
  for (int i = 0; i < SIZE; ++i) {
    this->numThings[i] = numThings[i];
  }
}
int GetNumThings() {
  return *thingsPtr;
}

// Calling GetNumThings() in my Print() function outputs garbage

private:
int numThings[SIZE];
int* thingsPtr = numThings;