human
Lexicographically smallest substring with maximum occurrences containing a ' s ▁ and ▁ b ' s only | Function to Find the lexicographically smallest substring in a given string with maximum frequency and contains a ' s ▁ and ▁ b ' s only ..
To store frequency of digits.
size of string.
Take lexicographically larger digit in b.
get frequency of each character.
If no such string exits.
Maximum frequency.
Driver program"
How can the above be solved in Python?

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What is a code to lexicographically smallest substring with maximum occurrences containing a ' s ▁ and ▁ b ' s only and the other steps required?
assistant
#Here is code to lexicographically smallest substring with maximum occurrences containing a ' s ▁ and ▁ b ' s only and the other steps required.
 def maxFreq ( s , a , b ) :
	fre = [ 0 for i in range ( 10 ) ]
	n = len ( s )
	if ( a > b ) :
		swap ( a , b )
	for i in range ( 0 , n , 1 ) :
		a = ord ( s [ i ] ) - ord ( '0' )
		fre [ a ] += 1
	if ( fre [ a ] == 0 and fre [ b ] == 0 ) :
		return - 1
	elif ( fre [ a ] >= fre [ b ] ) :
		return a
	else :
		return b
if __name__ == ' _ _ main _ _ ' :
	a = 4
	b = 7
	s = "47744"
	print ( maxFreq ( s , a , b ) )