Please help. Dont understand $.$The code has following $4$ functions:

$1)$ div$\_$hash$($int key, int M$)$: divides key k with M size of hash table and use remainder of it$,$ returns hash value

h$($K$)=$ k mod M

k $=12345$

M $=95$

h$(12345)=12345$ mod $95$

$=90$

$2)$ mid$\_$sqr$\_$hash$($int key, int M$)$: it has $2$ steps:

$1)$ Square the key k$,$ which is k$*$k$.$

$2)$ Take digits from square of key by dividing it by M and further mode by M$,$ return hash value

h$($K$)=$ h$($k x k$)$

k $=60$

M $=100$

k x k $=60$ x $60$

$=3600$

h$(60)=60//100\%100$

The hash value obtained is $60$

$3)$ double$\_$hash $($int key, int M$)$:

h$1($key$)=$ key$\%$M

h$2($key$)=1+($key$\%13)$

rehash$($key$)=$ h$1($key$)+$i$*$h$2($key$)$ i starts from $1$ repeat untill you get hashvalue which is palindrome number

example : key $=12345$

M $=1000$

h$1(12345)=345$

h$2(12345)=1+(12345\%13)=1+8=9$

i $=1$ rehash $=345+1*9=354354$ is not palindrome

i$=2$ rehash $=345+18=363$ is palindrome stop

if i$>5$ and rehash value is not palindrome then make reverse of rehash as hash value.

return hash value

$4)$ mult$\_$hash$($int key, int A$)$:

Perform following steps:

$1)$ Choose a value A from $0$