Calculate suffix sum and compare it with prefix sum . Update ans accordingly .
suffSum [ n - 1 ] = arr [ n - 1 ] NEW_LINE if ( preSum [ n - 1 ] == suffSum [ n - 1 ] ) : NEW_LINE INDENT ans = max ( ans , preSum [ n - 1 ] ) NEW_LINE DEDENT for i in range ( n - 2 , - 1 , - 1 ) : NEW_LINE INDENT suffSum [ i ] = suffSum [ i + 1 ] + arr [ i ] NEW_LINE if ( suffSum [ i ] == preSum [ i ] ) : NEW_LINE INDENT ans = max ( ans , preSum [ i ] ) NEW_LINE DEDENT DEDENT return ans NEW_LINE