human
Give me a code to count ways to partition a string such that both parts have equal distinct characters and the other steps required given the following:
Count ways to partition a string such that both parts have equal distinct characters | Function to count the number of ways to partition the string such that each partition have same number of distinct character.
Prefix and suffix array for distinct character from start and end.
To check whether a character has appeared till ith index.
Calculating prefix array.
Character appears for the first time in string.
Character is visited.
Resetting seen for suffix calculation.
Calculating the suffix array.
Character appears for the first time.
This character has now appeared.
Loop to calculate the number partition points in the string.
Check whether number of distinct characters are equal.
Driver Code"
How can the above be solved in Python?
assistant
#Here is code to count ways to partition a string such that both parts have equal distinct characters and the other steps required.
 def waysToSplit ( s ) :
	n = len ( s ) ;
	answer = 0 ;
	prefix = [ 0 ] * n ;
	suffix = [ 0 ] * n ;
	seen = [ 0 ] * 26 ;
	for i in range ( n ) :
		prev = prefix [ i - 1 ] if ( i - 1 >= 0 ) else 0 ;
		if ( seen [ ord ( s [ i ] ) - ord ( ' a ' ) ] == 0 ) :
			prefix [ i ] += ( prev + 1 ) ;
		else :
			prefix [ i ] = prev ;
		seen [ ord ( s [ i ] ) - ord ( ' a ' ) ] = 1 ;
	seen = [ 0 ] * len ( seen ) ;
	suffix [ n - 1 ] = 0 ;
	for i in range ( n - 1 , 0 , - 1 ) :
		prev = suffix [ i ] ;
		if ( seen [ ord ( s [ i ] ) - ord ( ' a ' ) ] == 0 ) :
			suffix [ i - 1 ] += ( prev + 1 ) ;
		else :
			suffix [ i - 1 ] = prev ;
		seen [ ord ( s [ i ] ) - ord ( ' a ' ) ] = 1 ;
	for i in range ( n ) :
		if ( prefix [ i ] == suffix [ i ] ) :
			answer += 1 ;
	return answer ;
if __name__ == " _ _ main _ _ " :
	s = " ababa " ;
	print ( waysToSplit ( s ) ) ;