Articles

Fibonacci Series

C++ | 9/23/2020 8:35:57 AM

Fibonacci Series :
                      If you get the next number with sum of previous numbers then you can say it is fibonacci series.Let's start

        1. Finbonacci series with for loop
        2. Finbonacci series with while loop
        3. Finbonacci series with recursion               

Finbonacci series with for loop

using namespace std;
#include <conio.h>; 
#include <iostream>;

int main() 
{ 
int input;
int fib1 = 0, fib2 = 1, fib3;
cout<<"Please enter number"<<endl;
cin>>input;
cout<<fib1<<" "<<fib2<<" ";
for(int i =2; i < input; i++) //start the loop from 2 because 0 and 1 already printed by intialization
{
fib3 = fib1 + fib2;
cout<<fib3<<" ";

fib1 = fib2;
fib2 = fib3;
}
 getch(); 
return 0;
}

  Output : Please enter number
           10
           0 1 1 2 3 5 8 13 21 34
 
                 

Finbonacci series with while loop

using namespace std;
#include <conio.h>; 
#include <iostream>;

int main() 
{ 
int input;
int fib1 = 0, fib2 = 1, fib3;
cout<<"Please enter number"<<endl;
cin>>input;
cout<<fib1<<" "<<fib2<<" ";
int i =2; //start the loop from 2 because 0 and 1 already printed by intialization
while(i < input) 
{
fib3 = fib1 + fib2;
cout<<fib3<<" ";

fib1 = fib2;
fib2 = fib3;
i++;
}
 getch(); 
return 0;
}

  Output : Please enter number
           10
           0 1 1 2 3 5 8 13 21 34
 
                 

Finbonacci series with recursion

using namespace std;
#include <conio.h>; 
#include <iostream>;

void FibonacciSeries(int num, int input, int fib1, int fib2, int fib3)
{ 
if(num < input)
{ 
fib3 = fib1 + fib2; 
fib1 = fib2; 
fib2 = fib3;
cout<<fib3<<" "; 
FibonacciSeries(num + 1, input, fib1,fib2,fib3);
}
}
int main() 
{ 
static int input; 
static int fib1=0, fib2=1, fib3; 
cout<<"Please enter number"<<endl;
cin>>input;
cout<<fib1<<" "<<fib2<<" ";
FibonacciSeries(fib2 + 1, input, fib1, fib2, fib3); //fib2 + 1 because 2 numbers are already inialize

 getch(); 
return 0;
}

  Output : Please enter number
           10
           0 1 1 2 3 5 8 13 21 34