Program #1 (U1): Hello, World!

Program #2 (U1): Sum & Average + Operator Precedence

Program #3 (U1): Simple Interest (SI) & Compound Interest (CI)

Program #4 (U1): Type Conversion — Integer Division vs Casting

Program #5 (U1): Temperature Converter (°C ↔ °F)

Program #6 (U1): Maximum of Two Numbers (if/else)

Program #7 (U1): Even/Odd Checker

Program #8 (U1): Sign of a Number — positive/negative/zero (nested if-else)

Program #9 (U1): Largest of Three Numbers — nested if-else

Program #10 (U1): Absolute Value (no library)

Program #11 (U2): Leap Year Checker

Program #12 (U2): Grade Calculator from Percentage

Program #13 (U2): Menu-driven Calculator using switch

Program #14 (U2): Character Classifier using switch

Program #15 (U2): Sum of First N using three loops

Program #16 (U2): Prime Number Test with Early Exit

Program #17 (U2): Pattern Printing — Pyramids

Program #18 (U2): Count Digits in an Integer

Program #19 (U3): Linear Search in 1-D Array (function)

Program #20 (U3): Count Even and Odd in Array

Program #21 (U3): Largest and Second Largest (one pass)

Program #22 (U3): Reverse an Array In-Place (two pointers)

Program #23 (U3): Array Statistics via Functions

Program #24 (U3): Matrix Addition and Subtraction

Program #25 (U3): Matrix Multiplication with Compatibility Check

Program #26 (U3): Transpose and Symmetric Check

Program #27 (U3): String Utilities without <string.h>

Program #28 (U3): Count Character Categories in a String

Program #29 (U3): Count Words in a Sentence

Program #30 (U3): Palindrome String Check (case-insensitive)

Program #31 (U3): Call by Value vs Reference (swap)

Program #32 (U3): Iterate Array via Pointer Arithmetic (find max & index)

Program #33 (U3): Recursion — Factorial and Fibonacci

Program #34 (U3): Recursion — Sum from 1 to N

Program #35 (U3): Recursion — Reverse a String

Program #36 (U4): Pointer Basics & Array Sum via Pointer Traversal

Program #37 (U4): malloc — Dynamic Array and Mean

Program #38 (U4): realloc — Grow/Shrink a Dynamic Array

Program #39 (U4): struct Student {roll, name, marks} with Pass/Fail

Program #40 (U4): File Copy & Text Statistics