Linked list loop problem

[C++]

I have to add 2 polynomial equations. Each are stored in linked lists. eq_1 and eq_2 linklists are added and the total is stored in eq_1 linklist. But the problem is when im trying to add both equations, the 2nd for loop(eq_2) is looping once only. I mean when eq_1 loops for the 2nd time eq_2...