human
What is a code to count triplets from a sorted array having difference between adjacent elements equal to D and the other steps required given the following:
Count triplets from a sorted array having difference between adjacent elements equal to D | Function to count the number of triplets having difference between adjacent elements equal to D.
Stores the frequency of array elements.
Stores the count of resultant triplets.
Traverse the array.
Check if arr [ i ] - D and arr [ i ] - 2 * D exists in the Hashmap or not.
Update the value of ans.
Increase the frequency of the current element.
Return the resultant count.
Driver Code"
Solution in Python:
assistant
#Here is code to count triplets from a sorted array having difference between adjacent elements equal to D and the other steps required.
 def countTriplets ( D , arr ) :
	freq = { }
	ans = 0
	for i in range ( len ( arr ) ) :
		if ( ( ( arr [ i ] - D ) in freq ) and ( arr [ i ] - 2 * D ) in freq ) :
			ans += ( freq [ arr [ i ] - D ] * freq [ arr [ i ] - 2 * D ] )
		freq [ arr [ i ] ] = freq . get ( arr [ i ] , 0 ) + 1
	return ans
if __name__ == ' _ _ main _ _ ' :
	arr = [ 1 , 2 , 4 , 5 , 7 , 8 , 10 ]
	D = 1
	print ( countTriplets ( D , arr ) )