human
Recursive solution to count substrings with same first and last characters | Function to count substrings with same first and last characters.
base cases.
driver code"
Solution in Python:
 ... Can you provide a code to recursive solution to count substrings with same first and last characters and the other steps required?
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#Here is code to recursive solution to count substrings with same first and last characters and the other steps required.
 def countSubstrs ( str , i , j , n ) :
	if ( n == 1 ) :
		return 1
	if ( n <= 0 ) :
		return 0
	res = ( countSubstrs ( str , i + 1 , j , n - 1 ) + countSubstrs ( str , i , j - 1 , n - 1 ) - countSubstrs ( str , i + 1 , j - 1 , n - 2 ) )
	if ( str [ i ] == str [ j ] ) :
		res += 1
	return res
str = " abcab "
n = len ( str )
print ( countSubstrs ( str , 0 , n - 1 , n ) )