And Now comes my answer , hope atleast someone will find it helpful
I am still so not know why to include destination in hop count. as wiki says we should not
https://en.wikipedia.org/wiki/Hop_(networking) but solving this question by including destination
Level |
No of node |
1 |
1 |
2 |
2 |
3 |
4 |
4 |
8 |
path from level |
path to level |
no of such path |
length of path |
calculation |
4 |
4 |
8C2 = 28
(path from any of level 4 node to level 4 node)
|
6 |
|
4 |
3 |
8*4 |
5 |
|
4 |
2 |
8*2 |
4 |
|
4 |
1 |
8*1 |
3 |
|
3 |
3 |
4C2=6 |
4 |
|
3 |
2 |
4*2=8 |
3 |
|
3 |
1 |
4 |
2 |
|
2 |
2 |
1 |
2 |
|
2 |
1 |
2 |
1 |
|
1 |
1 |
1 |
0 |
|
|
|
|
|
|
Now multiply 'no of such path' with respective 'length of path' and divide by total of 'length of path' ANS is C