$[$Find the missing number$]$

$(8$ marks$)$ Yon are given an array of size $N-1$ consists of integeers ranging from $1$ to N$.$ One of

the elements is missing trom the given list. Assuming there are ne duptieates in the list.

a$)$ Design an eficient algorithm to find the missing number in the given array $[$Pseudocode$].$

b$)$ what is the time complexity of your algorithm

Note; The marks awardet will be proportional wo the efficiency of the stoggested algoritim.

Xxample:

Input:art $=(4,2,5,1)=N=5$

Output: $3.$

Explanation: The missing nenber between $1$ to $5$ is $3$

$1$