# FIBONACCI PRIME COMPOSITE USING C++!!!

|PRIME NUMBER||COMPOSITE NUMBER||FIBONACCI SERIES|

In this program, we going to check whether the given value is a Prime or Composite number and the Fibonacci series.

- Let’s start the program with the header file

** “#include<iostream>”** →input-output continuous bytes of data.

** “#include<stdlib.h>”** → stands for Standard Library. It has

**the**information of memory allocation/freeing functions.

** “using namespace std;”** →used to store variable value.

*“void primechk(int a)”*

*primechk →function name.

*void →returns data type.

*int a →argument of a (here a is variable);formal parameter.

- Next, we have declared j in integer; j is the local variable because we have defined that inside the primechk so, we can use j only inside the function.

**Prime and Composite Numbers:**

A

prime numberis anumberwhich has exactly two factors i.e. '1' andnumberitself. Acomposite numberhas more than two factors, which means apart from getting divided bynumber1 and itself, it can also be divided by at least one integer ornumber.

- At 1st we are using
; in if condition we have given a is equal to*“if condition”*(||)a is equal to*“0”**“1”*

|| → or operator.

- If we enter 0 (or) 1 the output will be displayed as neither prime nor composite.

*“else { for(j=2;j<a;j++)*

*{ if(a%j==0)*

*{ cout<<”\t COMPOSITE”;*

*break;} }*

*if(a==j)*

*cout<<”\t PRIME”; } }”*

- Now else part, except 0 or 1 if we give any other number it will go inside the else part.

## LOGIC OF THE CODE:

→so, it will again go into for loop.

Upto this the program is about prime and composite.

- Now we get into Fibonacci series.

FIBONACCI SERIES:

The

Fibonacci sequenceis aseriesofnumberswhere anumberis the addition of the last twonumbers, starting with 0, and 1. TheFibonacci Sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55

*“void fibo(int n)”*

fibo →function name.

*“{ int a=-1,b=1,c=0;*

*for(int i=1;i<=n;i++)*

*{ cout<<endl;*

*c=a+b;*

*cout<<c;*

*primechk(c);*

*a=b;*

*b=c; } }”*

## LOGIC OF THE CODE:

- Now get c=0 in the logic we have to check whether this 0 is prime or not ; c is the fibonacci result.

- Next, we going to control both prime, composite and fibonacci in main program.

*“int main()*

*{ int n;*

*cout<<”ENTER THE NUMBER OF REQUIRED FIBO TERMS”;*

*cin>>n;*

*cout<<”\n\tFIBONACCI SERIES\n”;*

*fibo(n);*

*return 0; }”*

- Given print staements are , “ENTER THE NUMBER OF REQUIRED FIBO TERMS and FIBONACCI SERIES”.

“fibo(n)” →calling fibonacci series function.