# C Programs

C programs are frequently asked in the interview. These programs can be asked from basics, array, string, pointer, linked list, file handling etc. Let's see the list of c programs.

## 1) Fibonacci Series

Write a c program to print fibonacci series without using recursion and using recursion.

Input: 10

Output: 0 1 1 2 3 5 8 13 21 34

## 2) Prime number

Write a c program to check prime number.

Input: 44

Output: not prime number

Input: 7

Output: prime number

## 3) Palindrome number

Write a c program to check palindrome number.

Input: 329

Output: not palindrome number

Input: 12321

Output: palindrome number

## 4) Factorial

Write a c program to print factorial of a number.

Input: 5

Output: 120

Input: 6

Output: 720

## 5) Armstrong number

Write a c program to check armstrong number.

Input: 153

Output: armstrong

Input: 22

Output: not armstrong

## 6) Sum of Digits

Write a c program to print sum of digits.

Input: 234

Output: 9

Input: 12345

Output: 15

## 7) Reverse Number

Write a c program to reverse given number.

Input: 123

Output: 321

## 8) Swap two numbers without using third variable

Write a c program to swap two numbers without using third variable.

Input: a=10 b=20

Output: a=20 b=10

## 9) Print "hello" without using semicolon

Write a c program to print "hello" without using semicolon

## 10) Assembly Program in C

Write a c program to add two numbers using assembly code.

## 11) C Program without main() function

Write a c program to print "Hello" without using main() function.

## 12) Matrix Multiplication

Write a c program to print multiplication of 2 matrices.

Input:

```first matrix elements:
1 1 1
2 2 2
3 3 3
second matrix elements
1 1 1
2 2 2
3 3 3
```

Output:

```multiplication of the matrix:
6 6 6
12 12 12
18 18 18
```

## 13) Decimal to Binary

Write a c program to convert decimal number to binary.

Input: 5

Output: 101

Input: 20

Output: 10100

## 14) Alphabet Triangle

Write a c program to print alphabet triangle.

Output:

```     A
ABA
ABCBA
ABCDCBA
ABCDEDCBA
```

## 15) Number Triangle

Write a c program to print number triangle.

Input: 7

Output:

```enter the range= 6
1
121
12321
1234321
123454321
12345654321
```

## 16) Fibonacci Triangle

Write a c program to generate fibonacci triangle.

Input: 5

Output:

```1
1	1
1	1	2
1	1	2	3
1	1	2	3	5
```

## 17) Number in Characters

Write a c program to convert number in characters.

Input: 5

Output: five

Input: 203

Output: two zero three   