DEV Community: Vinoth Kumar

sat notes

Vinoth Kumar — Sat, 03 Oct 2026 16:17:04 +0000

ARRAY IN PYTHON

Vinoth Kumar — Fri, 02 Oct 2026 16:04:21 +0000

EXAMPLE 01 :

l  = [0,0,2,4,0,0,3,5,0,0,0,0]

#[10,2,4,3,5,0,0,0]

[5,0,2,4,0,0,3,0]
[5,3,2,4,0,0,0,0]
[5,3,2,4,0,0,0,0]
[5,3,2,4,0,0,0,0]
[5,3,2,4,0,0,0,0]
[5,3,2,4,0,0,0,0]
[5,3,2,0,0,0,4,0]

i = 0 
j = 1
while i < len(l):
    if l[i] == 0:
        l[i], l[-j] = l[-j],l[i]
        if j < len(l)//2:
            j+=1
    i+=1
else:
    print(l)

EXAMPLE 02 :

 l  = [0,0,2,4,0,0,3,5,0,0,0,0]
 i = 0 
 j = 1
 while i < len(l):
     if l[i] == 0:
         l[i], l[-j] = l[-j],l[i]
         if j < len(l)//2:
             j+=1
     i+=1
 else:
     print(l)

wed notes

Vinoth Kumar — Wed, 30 Sep 2026 18:29:19 +0000

SET & DICTIONARY NOTES

Vinoth Kumar — Tue, 29 Sep 2026 17:14:10 +0000

MONDAY NOTES

Vinoth Kumar — Mon, 28 Sep 2026 16:41:56 +0000

SUNDAY NOTES

Vinoth Kumar — Sun, 27 Sep 2026 16:54:58 +0000

METHODS IN JAVA

Vinoth Kumar — Sat, 26 Sep 2026 17:24:13 +0000

METHODS :

Methods are blocks of code that perform a specific task. A method allows us to reuse code, improving both efficiency and organization. All methods in Java must belong to a class. Methods are similar to functions and expose the behavior of objects.

TYPES OF METHODS IN JAVA:

Predefined Method.
User-defined Method

1) PRE-DEFINED METHODS :

The method that is already defined in the Java class libraries. It is also known as the standard library method or built-in method.

2)** USER-DEFINED METHODS :**

Method written by the user or programmer is known as a user-defined method. These methods are modified according to the requirement.

CONSTRUCTOR IN JAVA

Vinoth Kumar — Fri, 25 Sep 2026 17:24:44 +0000

LIST IN PYTHON DAY 04

Vinoth Kumar — Thu, 24 Sep 2026 17:30:57 +0000

EXAMPLE 01 :

s = 'a1b2c3'
#output: abc123
# a1b2c3
# 123 

# abc123
alpha = ''
numbers = ''

for letter in s:
    if letter >='a' and letter <= 'z':
        alpha+=letter 

for letter in s:
    if letter >='0' and letter <= '9':
        numbers+=letter

print(alpha+numbers)

EXAMPLE 02 :

s = 'a1b2c3'

print(s[0] + chr(ord(s[0]) + int(s[1])))
print(s[2] + chr(ord(s[2]) + int(s[3])))
print(s[4] + chr(ord(s[4]) + int(s[5])))

EXAMPLE 03 :

s='a1b2c3'
letters = [char for char in s if char.isalpha()]
nums = [no for no in s if no.isdigit()]
output = ''.join(letters+nums)
print(output)

STATIC & NON-STATIC IN JAVA

Vinoth Kumar — Wed, 23 Sep 2026 17:14:53 +0000

STATIC VARIABLE IN JAVA :

A class-level variable that is declared using the static keyword. Instance variables, only one copy of a static variable is created and shared among all objects of the class.
It useful for storing common data.

EXAMPLE :

Public class Home{
  static string name = "RV";
  static int years = "25";
Public static void main(String[] args){
  System.out.println(Home.name);
}
}

NON-STATIC VARIABLE IN JAVA :

It's known as non-static variables and are declared in a class outside of any method, constructor, or block.
Instance variables are created when an object is instantiated and destroyed when the object is destroyed.

EXAMPLE :

Public class Home{
  string name = "RV";
  int years = "25";
Public static void main(String[] args){
  System.out.println(Home.name);
}
}

DIFFERENCE BETWEEN STATIC AND NON-STATIC VARIABLE :

JAVA DAY 02

Vinoth Kumar — Tue, 22 Sep 2026 17:56:38 +0000

PROGRAMMING PARADIGMS :

A method or style of solving problems using a programming language. It provides a structured approach and set of principles that guide how programs are designed and implemented.

PROCEDURAL LANGUAGE :

A software development method that is executed step by step in a certain manner. The sequence of tasks to be carried out in order to find a solution is of primary importance.

TYPES OF POP :

FORTRAN.
C.
BASIC.
Pascal.
ALGOL.
COBOL.

OBJECT ORIENTED PROGRAMMING LANGUAGE :

A programming paradigm that organizes software around objects rather than functions and logic.
An object contains both data (attributes) and methods (behavior), making programs more modular and reusable.

TYPES OF OOP :

Python
Java
C++
JavaScript
C#
Ruby
PHP
TypeScript
Kotlin
R

JAVA PROGRAMMING

Vinoth Kumar — Mon, 21 Sep 2026 17:16:11 +0000

JAVA :
A widely used programming language for building web, desktop, mobile, and enterprise applications. It is known for its simple syntax, portability, and powerful features that make development easier and more secure.

FEATURES OF JAVA :

Object-Oriented Programming.
Platform Independence.
Multithreading and Concurrency.