text: Find the most valued alphabet in the String | Python implementation of the approach ; Function to return the maximum valued alphabet ; Set the first and the last occurrence of all the characters to - 1 ; Update the occurrences of the characters ; Only set the first occurrence if it hasn 't already been set ; To store the result ; For every alphabet ; If current alphabet doesn 't appear  in the given string ; If the current character has the highest value so far ; Driver code
code: MAX = 26 NEW_LINE def maxAlpha ( str , len ) : NEW_LINE INDENT first = [ - 1 for x in range ( MAX ) ] NEW_LINE last = [ - 1 for x in range ( MAX ) ] NEW_LINE for i in range ( 0 , len ) : NEW_LINE INDENT index = ord ( str [ i ] ) - 97 NEW_LINE if ( first [ index ] == - 1 ) : NEW_LINE INDENT first [ index ] = i NEW_LINE DEDENT last [ index ] = i NEW_LINE DEDENT ans = - 1 NEW_LINE maxVal = - 1 NEW_LINE for i in range ( 0 , MAX ) : NEW_LINE INDENT if ( first [ i ] == - 1 ) : NEW_LINE INDENT continue NEW_LINE DEDENT if ( ( last [ i ] - first [ i ] ) > maxVal ) : NEW_LINE INDENT maxVal = last [ i ] - first [ i ] ; NEW_LINE ans = i NEW_LINE DEDENT DEDENT return chr ( ans + 97 ) NEW_LINE DEDENT str = " abbba " NEW_LINE len = len ( str ) NEW_LINE print ( maxAlpha ( str , len ) ) NEW_LINE