human
Count number of common elements between a sorted array and a reverse sorted array | Function to count the number of elements common in both the arrays.
Used to traverse array A [ ] and B [ ] from the front and the back.
Stores the count of numbers common in both array.
If A [ first ] is less than B [ second ].
Increment the value of first.
IF B [ second ] is less than A [ first ].
Decrement the value of second.
A [ first ] is equal to B [ second ].
Increment the value of count.
Increment the value of first.
Decrement the value of second.
Return the value of count.
Driver Code"
Solution in Python:

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What is a code to count number of common elements between a sorted array and a reverse sorted array and the other steps required?
assistant
#Here is code to count number of common elements between a sorted array and a reverse sorted array and the other steps required.
 def countEqual ( A , B , N ) :
	first = 0
	second = N - 1
	count = 0
	while ( first < N and second >= 0 ) :
		if ( A [ first ] < B [ second ] ) :
			first += 1
		elif ( B [ second ] < A [ first ] ) :
			second -= 1
		else :
			count += 1
			first += 1
			second -= 1
	return count
A = [ 2 , 4 , 5 , 8 , 12 , 13 , 17 , 18 , 20 , 22 , 309 , 999 ]
B = [ 109 , 99 , 68 , 54 , 22 , 19 , 17 , 13 , 11 , 5 , 3 , 1 ]
N = len ( A )
print ( countEqual ( A , B , N ) )