Skip to main content

Fibonacci series in C non recursive

Objective : To print given numbers of Fibonacci series. (1,1,2,3,5.....) non recursively.
Programming Logic: Its easy to print the above Fibonacci series in C. the number is always sum of previous 2 terms. This series starts with numbers 1,1. so next term is 1+1=2. Then next term is 1+2=3 and so on.
(It may be noted that series 1,3,4,7,11,18.... is also a Fibonacci series, but it starts with 1,3 )

Code : 
#include<stdio.h>
int main()
{
    int k;
    printf("\n enter number of terms to print=");
    scanf("%d",&k);
    fic(k);
    return(0);
}
void fic(int x)// x are number of terms to print
{
    int a,b,sum,i;
    a=b=1;
    printf("1,1,",sum);//first 2  terms
    for(i=0;i<x-2;i++)
    {
        sum=a+b;
        printf("%d,",sum);
        a=b;
        b=sum;    
    }
}

It may be noted that using a non recursive way to calculate Fibonacci series in C provides faster calculations as compared with recursive method. As recursive program have a large overhead of function calls. Also the recursive way is very unoptimised since it doesn't uses the last 2 values that have been calculated already..
Labels:

Popular posts from this blog

calculating leap year in c using if else

Most new students get really confused when it comes to calculating Leap year in C. It is given as an exercise to enhance their knowledge about using if else usages. This can be calculated using Logical operators too. But using if else provides clearer ways to calculate it. Both of the methods can be implemented in C/C++ program. Here we will discuss the if else method in C/C++
Read more

Overloading Unary Operator in C++

In this Example I will demonstrate overloading a unary operator. The overloading is done in similar way as we did for binary operator. In this example I will be using a Vector Class. The operator we are going to over load is the unary "~" (tilde) operator. although you can use any unary overloadable operator. Method: In this example the overloaded operator will be the part of the class i.e. the over loaded definition will be a member function. (As we know overloading can be done using non member functions too). So the unary operator will not have any arguments in it. We will overload ~ operator so that it will reflect the vector so that its z component becomes x component and vice versa. So input vector will be 2i+3j+5k and its output vector will be 5i+3j+2k. although you can do anything you like. Code: # include < iostream > using namespace std ; class vector { int x , y , z ;      public : vector ( ) { x = y = z = 0 ; ...
Read more