在双链表中的指定参数之前删除项目

Question

I'm not sure how to link a two nodes together. I understand that in order to link the first one with the third one (because i'm removing the second one), I use something like crt.next = crt.next.next but how am i supposed to do link the node that node back?

Example:

X1 <> x2 <> X3 <> x4 <> x5 I want to remove x3. so i link x2 to x4 by crt.next = crt.next.next I don't know how to linke x4 back to x2.

Thanks

Answer 1

After you do

crt.next = crt.next.next

you can do:

crt.next.prev = crt

since you want to link crt as the previous link from crt.next.

Answer 2

Linking x4 to x2 would be

crt.next.next.prev=crt;

then you need to free x3 memory

free(x3);