Programming Example
Program to generate Fibonacci series using the recursive and iterative method
Program to generate Fibonacci series using the recursive and iterative method
#include<stdio.h>
int fib(int n);
int TailRecursiveFib(int n);
int TRfib(int n, int next, int result);
int Ifib(int n);
main( )
{
int nterms, i;
printf("Enter number of terms : ");
scanf("%d", &nterms);
for(i=0; i<nterms; i++)
printf("%d ", fib(i));
printf("\n");
for(i=0; i<nterms; i++)
printf("%d ", TailRecursiveFib(i));
printf("\n");
Ifib(nterms);
printf("\n");
}
/*Recursive*/
int fib(int n)
{
if(n==0 || n==1)
return(1);
return(fib(n-1) + fib(n-2));
}
int TailRecursiveFib(int n)
{
return TRfib(n,1,1);
}
int TRfib(int n, int next, int result)
{
if(n == 0)
return(result);
return TRfib(n-1, next+result, next);
}
/*Iterative*/
int Ifib(int n)
{
int i, x=0, y=1, z;
printf("%d ", y);
for(i=1; i<n; i++)
{
z=x+y;
printf("%d ", z);
x = y;
y = z;
}
}Enter number of terms : 10
1 1 2 3 5 8 13 21 34 55
1 1 2 3 5 8 13 21 34 55
1 1 2 3 5 8 13 21 34 55
Press any key to continue . . .
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.