C Fundamentals Practice Programs (Level 1) Guide

This page lists Level 1 C topic-wise practice. Each topic uses two columns: simple C programs (left) and CodeChef / LeetCode links (right). Work in order—operators and control flow first, then loops, arrays, strings, pointers, and structures. Always read the official statement and constraints on the platform.

1. Operators

Simple C programs

#	Program idea
1	Swap two numbers using a third variable, without a third variable, and in a single line.
2	Swap two numbers using bitwise operators.
3	Maximum of two numbers.
4	Simple and compound interest.
5	Celsius to Fahrenheit.
6	Even or odd using bitwise operators.
7	Total and average of three subject marks.
8	Area of circle, triangle, rectangle, and square.
9	Perimeter of circle, triangle, rectangle, and square.
10	Even or odd using the conditional operator.

CodeChef practice

Open each problem on CodeChef (search or direct practice link).

2. Control statements

Simple C programs

#	Program idea
1	Largest of three numbers using simple `if`, `if-else`, else-if ladder, and nested `if`.
2	Leap year check using the same four styles.
3	Vowel or consonant using the same four styles.
4	Grade system from student marks.
5	Divisible by 5 and 11.
6	Electricity bill using the same control-flow styles.
7	Triangle types (validity and classification).
8	Sort three numbers.
9	Character is digit, alphabet, or special symbol.
10	Largest of three using the conditional operator.

CodeChef & LeetCode

Practice problems matching your syllabus names.

3. Switch statement

Simple C programs

#	Program idea
1	Calculator using `switch`.
2	Day of week.
3	Month name.
4	Vowel or consonant.
5	Menu-driven program.
6	Grade system.
7	ATM menu.
8	Given digit in characters.

LeetCode

Classic problems that reinforce switch-like mapping logic.

4. Loops

Simple C programs

#	Program idea
1	Print N to 1.
2	Sum of N numbers.
3	Factorial.
4	Fibonacci series.
5	Reverse a number.
6	Palindrome number.
7	Prime number in four different ways.
8	Multiplication table.
9	Count digits in a number.
10	Armstrong number.

LeetCode & CodeChef

Digit / number tricks align with these platform problems.

LCAdd Digits (sum of digits)
LCReverse Integer (reverse the number)
LCPower of Three
LCCount Primes
LCHappy Number
CCTCS Examination

5. Arrays (1D)

Simple C programs

#	Program idea
1	Print array in reverse order.
2	Sum of elements.
3	Largest and smallest element.
4	Print middle element.
5	Reverse the array.
6	Count even and odd.
7	Linear search.
8	Copy array.
9	Binary array or not (all 0/1).
10	Frequency count.

CodeChef & LeetCode

Arrays practice on both platforms.

6. Arrays (2D)

Simple C programs

#	Program idea
1	Matrix addition.
2	Matrix subtraction.
3	Matrix multiplication.
4	Transpose matrix.
5	Diagonal sum.
6	Identity matrix check.
7	Sparse matrix.
8	Upper triangular matrix.
9	Lower triangular matrix.
10	Binary matrix or not.

LeetCode & CodeChef

Matrix problems; “Flipping an Image” appears twice in the syllabus—practice once.

7. Strings

Simple C programs

#	Program idea
1	String length (manual / library).
2	Copy string.
3	Compare strings.
4	Character and word count.
5	Palindrome string.
6	Count vowels and consonants.
7	Case conversion.
8	Remove common letters from two strings.
9	Character frequency.
10	Replace a letter with another.

CodeChef & LeetCode

String drills on both platforms.

8. Pointers & dynamic memory

Simple C programs

#	Program idea
1	Pointer basics.
2	Swap using pointers.
3	Array using pointers.
4	Pointer arithmetic.
5	Pointer to pointer.
6	`malloc` demo.
7	`calloc` demo.
8	`realloc` demo.
9	Free memory safely.
10	Dynamic array.

LeetCode

Array manipulation with index / two-pointer ideas.

9. Structures

Simple C programs

#	Program idea
1	Student details.
2	Employee record.
3	Array of structures.
4	Pointer to structure.
5	Nested structure.
6	Structure comparison.
7	Passing structure to function.
8	`typedef` usage.

LeetCode

Object-style problems that map well to structs in C.

Content structure and exercise titles are taken from the internal syllabus document C TOPIC WISE PROBLEM SOLVING QUESTIONS (Level 1, C language). Platform problem names are for discovery—always read the official statement and constraints on CodeChef or LeetCode.

Back to Engineers Hub — topic-wise practice