c++ structures pointers reference value being changed

Question

I am implementing A* path finding in c++. The issue which I am facing is related with pointers and references being used with structures.

After it exits the for loop, it traverses the openList (vector) and sets the currentNode to the element with the least F value, F is of type int.

When the currentNode gets changed, the parent which was earlier in the for loop assigned by the currentNode, gets changed

NavigationNode currentNode;

currentNode.x = 1;
currentNode.y = 2;

parent = &currentNode

if I update the currentNode to another value

currentNode.x =23;
currentNode.y = 1;

the parent will also get changed. I understand that parent is holding the address of currentNode. so any changes get reflected. But I want to know how can I make the parent value not to be changed. if I later update the currentNode

I have a struct declared as

struct NavigationNode{
    int x, y; 
    float f, g, h;
    int value;
    NavigationNode *parent;
};

I create a startNode of NavigationNode

NavigationNode startNode;
startNode.x = START_X;
startNode.y = START_Y;
startNode.g = 0;
startNode.f = 0;

I inserted it into vector named openList

vector<NavigationNode> openList;
openList.push_back(startNode);

NavigationNode currentNode;

Then I start the finding the path

while (!openList.empty())
{       
    for (auto i = openList.begin(); i != openList.end(); ++i)
    {
        if (i == openList.begin() || (*i).f <= currentNode.f)
        {
            currentNode = (*i);
        }
    }

    for (int i = 0; i < 8; i++)
    {
         NavigationNode nextNode;
         nextNode.x = xChange;
         nextNode.y = yChange;

         // some logic operations
         // assign the currentNode to the parentNode 

         nextNode.parent = &currentNode;
         nextNode.value = map[xChange][yChange];

         openList.push_back(nextNode);
     }
}

Answer 1

The reason why currentNode changes get reflected in parent, is because I am assigning the address to parent. so any changes get reflected. However, now I create currentNode, as a pointer, it will have different address. and have declared the rest as pointers as well

   NavigationNode *startNode;
   startNode->x = START_X;
   startNode->y = START_Y;
   startNode->g = 0;
   startNode->f = 0;


   vector<NavigationNode*> openList;
   openList.push_back(*startNode);

    NavigationNode *currentNode = new NavigationNode;



     while (!openList.empty())
     {

    // sort the vector by increasing F values, so the lowest F values will be at the first location
    //  sort(openList.begin(), openList.end(), compareByF);
         for (auto i = openList.begin(); i != openList.end(); ++i){

             if (i == openList.begin() || (*i)->f <= currentNode->f){
               currentNode = (*i);
             }
         }

           for (int i = 0; i < numberOfDirections; i++)
            {
                NavigationNode *nextNode = new NavigationNode;
                nextNode->x = xChange;
                nextNode->y = yChange;

                // some logic operations
                // assign the currentNode to the parentNode 

               nextNode->parent = currentNode;
               nextNode->value = map[xChange][yChange];

               openList.push_back(nextNode);

             } // end for loop

       }// end while loop