For example, all of naveen's friends with letter B, C, D, E, F, G, H. Since, we know that every naveen's friends responded naveen question with
$7$ distinct positive integers, we can guess that
B shook hands $7$ times
C shook hands $6$ times
D shook hands $5$ times
E shook hands $4$ times
F shook hands $3$ times
G shook hands $2$ times
H shook hands $1$ time
B shook hands with all of Naveen's friends, including Naveen.
B $\rightarrow$ A, C, D, E, F, G, H
C shook hands with all of Naveen's friends, including Naveen except H.
C $\rightarrow$ A, B,D, E, F, G
D shook hands with all of Naveen's friends, including Naveen and except G and H.
D $\rightarrow$ A, B, D, E, F
E shook hands with all of Naveen's friends, including Naveen and except F, G, H.
E $\rightarrow$ A, B, C, D
F only shook hands with B, C and D.
So, A shook hands with B, C, D, E ($4$ times)