GATE | GATE CS 1996 | Question 66

Consider the following program that attempts to locate an element x in a sorted array a[ ] using binary search. Assume N>1. The program is erroneous. Under what conditions does the program fail?

var i,j,k: integer;  x: integer;
    a: array; [1....N] of integer;
begin	i:= 1; j:= N;
repeat	
    k:(i+j) div 2;
    if a[k] < x then i:= k 
    else j:= k 
until (a[k] = x) or (i >= j);
    
if (a[k] = x) then
    writeln (\'x is in the array\')
else
    writeln (\'x is not in the array\')
end;

(A)

(B)

(C)

(D)