text: Given a string and an integer k , find the kth sub | Function to prints kth sub - string ; Total sub - strings possible ; If k is greater than total number of sub - strings ; To store number of sub - strings starting with ith character of the string ; Compute the values ; substring [ i - 1 ] is added to store the cumulative sum ; Binary search to find the starting index of the kth sub - string ; To store the ending index of the kth sub - string ; Print the sub - string ; Driver code
code: def Printksubstring ( str1 , n , k ) : NEW_LINE INDENT total = int ( ( n * ( n + 1 ) ) / 2 ) NEW_LINE if ( k > total ) : NEW_LINE INDENT print ( " - 1" ) NEW_LINE return NEW_LINE DEDENT substring = [ 0 for i in range ( n + 1 ) ] NEW_LINE substring [ 0 ] = 0 NEW_LINE temp = n NEW_LINE for i in range ( 1 , n + 1 , 1 ) : NEW_LINE INDENT substring [ i ] = substring [ i - 1 ] + temp NEW_LINE temp -= 1 NEW_LINE DEDENT l = 1 NEW_LINE h = n NEW_LINE start = 0 NEW_LINE while ( l <= h ) : NEW_LINE INDENT m = int ( ( l + h ) / 2 ) NEW_LINE if ( substring [ m ] > k ) : NEW_LINE INDENT start = m NEW_LINE h = m - 1 NEW_LINE DEDENT elif ( substring [ m ] < k ) : NEW_LINE INDENT l = m + 1 NEW_LINE DEDENT else : NEW_LINE INDENT start = m NEW_LINE break NEW_LINE DEDENT DEDENT end = n - ( substring [ start ] - k ) NEW_LINE for i in range ( start - 1 , end ) : NEW_LINE INDENT print ( str1 [ i ] , end = " " ) NEW_LINE DEDENT DEDENT if __name__ == ' _ _ main _ _ ' : NEW_LINE INDENT str1 = " abc " NEW_LINE k = 4 NEW_LINE n = len ( str1 ) NEW_LINE Printksubstring ( str1 , n , k ) NEW_LINE DEDENT