Maths for DSA – Part 1 | Count Digits | Number System Basics

Lecture Resources
https://github.com/Tiwarishashwat/Jav...

In this lecture, we begin Maths for DSA – Part 1, where we cover number system basics that are extremely important for DSA problems and coding interviews.

Many beginners struggle with math-based logic in DSA — this lecture focuses on clear understanding + practical implementation.

Topics covered in this video:

Why Maths is important for DSA

Number system basics for problem solving

How to count digits in a number

Counting digits using logarithmic formula

Handling special cases:

Positive numbers

Zero

Negative numbers

Time complexity analysis of digit-count logic

Clean and interview-ready Java implementation

This lecture will help you build strong mathematical intuition, which is required for:

Arrays & Strings problems

Recursion

Binary Search

Competitive programming

This video is part of my Java + DSA course by ShashCode, designed for:

DSA beginners

College students

Placement & interview preparation

Strong problem-solving foundations

👉 Watch till the end to avoid common mistakes in digit-based problems.

0:00 - Introduction
0:15 - find the number of digits using log formula
1:00 - find the number of digits using modulo and division
2:52 - find digits code
8:59 - appending digits
13:57 - insert digit at front
19:40 - reverse a number
25:57 - odd or even numbers
28:02 - find power
33:25 - Fast Exponentiation
42:31 - Number System
45:27 - Any base to decimal
57:19 - Decimal to any base
1:04:03 - Outro