# datlib
This is a python package containing useful classes and functions of data structures and algorithms.
## Installation
Run the following to install:
'''python
pip install datlib
'''
## Usage
There are many modules inside this package.
###1. rangeQueries module
This module contains a class name SegmentTree.
The constructor of the class takes following arguments :
(a) A function **combine**
This takes two arguments a and b. This function takes care of
the combination of the values of child nodes into a parent node.
(b) A variable **identityVal**
An identity value for filling the empty nodes in the segment tree
array and for the case when the query is completely outside the
range.
(c) A list **l**
This contains the list for which you have to make the SegmentTree.
You can make the segment tree in following way :
'''python
from rangeQueries import SegmentTree
def combine(a,b):
return a+b
l = [1,2,3,4,5,6,7,8]
identityVal = 0
s = SegmentTree(l,identityVal,combine)
'''
You can call following methods on your segment tree :
(a) query(qs,qe)
This method will take two parameters qs and qe. And will perform
query for the range.
(b) pointUpdate(val,qi)
This method will take two parameters qi and val,where qi is the
index of the given list **l** on which we will update the value
to **val**.This will update the your segment tree.
(c) rangeUpdate(qs,qe,val)
This method will take three parameters qs,qe and val.This method
will update the values to **val** from index **qs** to **qe**.
This will update the your segment tree.
###2. numbertheory module
This module contains following functions :
Here **n** is the number.
(a) primefactors(n)
This function will return all the prime factors of a number.
(b) chkPrime(n)
This function will check if a number is prime or not.
(c) divisors(n)
This function will return all the divisors of a number.
(d) powerModulo(x,y,M)
This function will calculate x^y modulo M.
###3. graphs module
This module contains following functions :
(a) bfs(start,graph)
This function will take two arguments start and graph.
Start is the source node which can be a tuple,number or a string.
graph is a dictionary which contains the adjacency list of the nodes.
This function will return a dictionary containing distance of all the
nodes from the source node.
(b) dfs(start, graph)
This function will take two arguments start and graph.
Start is the source node which can be a tuple,number or a string.
graph is a dictionary which contains the adjacency list of the nodes.
This function will contain a set of all the nodes that can be reched
from start.
