human
Reverse a subarray to maximize sum of even | Function to return maximized sum at even indices.
Stores difference with element on the left.
Stores difference with element on the right.
Compute and store left difference.
For first index.
If previous difference is positive.
Otherwise.
For the last index.
Otherwise.
For first index.
If the previous difference is positive.
Driver Code"
Solution in Python:
 ... Give me a code to reverse a subarray to maximize sum of even and the other steps required?
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#Here is code to reverse a subarray to maximize sum of even and the other steps required.
 def maximizeSum ( arr ) :
	n = len ( arr )
	sum = 0
	for i in range ( 0 , n , 2 ) :
		sum += arr [ i ]
	leftDP = [ 0 ] * ( n )
	rightDP = [ 0 ] * ( n )
	c = 0
	for i in range ( 1 , n , 2 ) :
		leftDiff = arr [ i ] - arr [ i - 1 ]
		if ( c - 1 < 0 ) :
			leftDP [ i ] = leftDiff
		else :
			if ( leftDP [ i ] > 0 ) :
				leftDP [ i ] = ( leftDiff + leftDP [ i - 1 ] )
			else :
				leftDP [ i ] = leftDiff
		rightDiff = 0
		if ( i + 1 >= len ( arr ) ) :
			rightDiff = 0
		else :
			rightDiff = arr [ i ] - arr [ i + 1 ]
		if ( c - 1 < 0 ) :
			rightDP [ i ] = rightDiff
		else :
			if ( rightDP [ i ] > 0 ) :
				rightDP [ i ] = ( rightDiff + rightDP [ i - 1 ] )
			else :
				rightDP [ i ] = rightDiff
		c += 1
	maxm = 0
	for i in range ( n // 2 ) :
		maxm = max ( maxm , max ( leftDP [ i ] , rightDP [ i ] ) )
	return maxm + sum
if __name__ == ' _ _ main _ _ ' :
	arr = [ 7 , 8 , 4 , 5 , 7 , 6 , 8 , 9 , 7 , 3 ]
	ans = maximizeSum ( arr )
	print ( ans )