In the code below, the user is asked to input a number. The code checks whether the number is even or odd. There is a missing variable or number, indicating by the $\_\_\_\_\_\_\_\_\_\_\_.$ What should replace the $\_\_\_\_\_\_\_\_\_\_$ for this code to execute properly?

read $-$p "Enter a number: $"$ num

if $[$ $$(($num $\%2))-$eq $\_\_\_\_\_\_\_\_\_\_\_]$ then

echo "This number is even."

else

echo "This number is odd."

fi