Your boss has instructed you to make up a medium for growing Gram-negative prokaryotes. She wants you to be able to grow 100 mg/l of volatile suspended solids. You looked up some papers on the microorganisms and found that the empirical chemical formula for them is C_5H_7O_2NP_0.1. What are the minimum concentrations of NH^+_4 -N and PO_4-P that you must add to your medium? Solution Phosphorus and Nitrate were found at a ratio of 1:10 in microbes as studied in the example. So 10+1=11 parts weighs 100 mg, i.e. 100/11=9.090 mg PO4-P and rest 90.909 mg NH4+-N in 1 litre is suggested for your medium..

1. [Python] [Singly-linked list] [Element insertion] Consider the following singly linked list.
Provide the instructions to insert the new node immediately following the node containing 52.
Do not use a loop or any additional external references.
Solution
# Node class
class Node:
# Function to initialise the node object
def __init__(self, data):
self.data = data # Assign data
self.next = None # Initialize next as null
class LinkedList:
# constructor to initialize head
def __init__(self):
self.head = None
# Function to insert a new node at the beginning
def push(self, new_data):
new_node = Node(new_data)
new_node.next = self.head
self.head = new_node
def insert_After(self, prev_node, new_data):
# check if given prev_node exists
if prev_node is None:
print "previous node not in the LinkedList."

2. return
# create new node and put the data
new_node = Node(new_data)
new_node.next = prev_node.next
prev_node.next = new_node
#function to print the linked list
def print_the_List(self):
temp = self.head
while (temp):
print temp.data,
temp = temp.next
# Code execution starts
if __name__=='__main__':
# Start with the empty list
list = LinkedList()
# Insert 36 at the beginning
list.push(36);
# Insert 18 at the beginning. So linked list becomes 18->36->None
list.push(18);
# Insert 52 at the beginning. So linked list becomes 52->18->36->None
list.push(52);
list.push(2);
list.push(73);
print 'The list is:',
list.print_the_List()

3. # Insert 22, after 52. The linked list will becomes 73->2->22->52->18->36->None None
list.insert_After(list.head.next, 22)
print ' The list after inserting 22 is:',
list.print_the_List()