Discover data structures and algorithms using Python. Gain insights into solving real-world problems and typical interview questions with detailed reviews, explanations, and hands-on coding exercises.

Data structures and algorithms are among the most fundamental concepts of Computer Science. Whether it’s real-world problems you’re trying to solve or the typical coding question asked in an interview, almost every problem requires you to demonstrate a deep understanding of data structures and algorithms. 

This course is a detailed review of some of the most common data structures and algorithms that you’ll see in interviews and your everyday work. With implementation details, thorough explanations, and hands-on coding exercises, you’ll quickly gain the confidence you need to solve any problem, no matter the situation.

Data Structures and Algorithms in Python

In this lesson, we will solve the following problem:

You are given some integer as input, (i.e. ... -3, -2, -1, 0, 1, 2, 3 ...) and you have to convert the integer you are given to a string. 
Examples:
```
    Input: 123
    Output: "123"
    Input: -123
    Output: "-123"
```


Note that you cannot make use of the built-in `str` function:


Before diving into the implementation of the solution, we need to get familiar with the following functions:

1. `ord()`
2. `chr()`

You might be able to recall `ord()` from one of the previous lessons. `ord()` returns an integer which represents the Unicode code point of the Unicode character passed into the function. On the other hand, `chr()` is the exact opposite of `ord()`.  `chr()` returns a character from an integer that represents the Unicode code point of that character.


## Prints 48 which is the Unicode code point of the character '0'
print(ord('0'))
## Prints the character '0' as 48 is Unicode code point of the character '0'
print(chr(ord('0')))
## Prints 49 
print(ord('0')+ 1)
## Prints 49 which is Unicode code point of the character '1'
print(ord('1'))
## Prints the character '2' as 50 is Unicode code point of the character '2'
## ord('0') + 2  = 48 + 2 = 50
print(chr(ord('0')+ 2))
## Prints the character '3' as 51 is Unicode code point of the character '3'
## ord('0') + 3  = 48 + 2 = 51
print(chr(ord('0')+ 3))

From the above coding example, you can observe the following pattern:

```
ord('0') = 48
ord('1') = ord('0') + 1 = 48 + 1 = 49 
ord('2') = ord('0') + 2 = 48 + 2 = 50 

chr(ord('0')) = chr(48) = '0' 
chr(ord('0') + 1) = chr(48 + 1) = chr(49) = '1' 
chr(ord('0') + 2) = chr(48 + 2) = chr(50) = '2' 

```

At this point, you must be familiar with the workings of `ord` and `chr` functions. Let's discuss the actual implementation now. 

# Implementation

In this lesson, you will learn how to convert an integer to a string in Python. 

Introduction

Stack

Singly Linked Lists

Circular Linked Lists

Doubly Linked Lists

Arrays

Binary Trees

Binary Search Trees

Binary Search

Recursion

String Processing

Integer to String