You are surprised?
I don't know what value you are passing through as the
, but you then proceed to nest loops that will be at least width^5 iterations of the inner loop. (More, probably, since you don't clear your class level lists before you add new elements, and we can't see the number of elements in V) So, if your width is 5, then your inner loop is executed 3125 times. If it is 20, then it;'s 3,200,000 times round, and so forth, each time adding elements to a list...
Your form will do nothing until all iterations are complete. There are things you can do to prevent that, but first I think you need to look at this and work out if that is what you actually intended...
how can i send a textbox value from one form to another form and assign tetbox value to one variable???"
Depends on the relationship between the forms.
You don't send the textbox, you send the Text property string and let the other form decide what to do with it.
Have a look at these: one of them will describe the relationship and explain what to do.
Transferring information between two forms, Part 1: Parent to Child
Transferring information between two forms, Part 2: Child to Parent
Transferring information between two forms, Part 3: Child to Child