Following is an incorrect pseudocode for the algorithm which is supposed to determine whether a sequence of parentheses is balanced:

declare a character stack

while $($ more input is available$)$

$\{$

read a character

if $($ the character is a $\text{'}(\text{'})$

push it on the stack

else if $($ the character is a $\text{'})\text{'}$ and the stack is not empty $)$

pop a character off the stack

else

print "unbalanced" and exit

$\}$

print "balanced"

Run on IDE

Which of these unbalanced sequences does the above code think is balanced?

Your answer:

$(0)(0)$

$(0(0))$

$(0)$