Before going to the program first let us understand what is a Fibonacci Series?
Fibonacci Series:
Fibonacci series is nothing but a Series of Numbers which are found by adding the two preceding(previous) Numbers.
For Example,
0,1,1,2,3,5,8,13,21 is a Fibonacci Series of length 9.
For more understanding you can check out the following link:
https://www.mathsisfun.com/numbers/fibonacci-sequence.html
Program code to Display Fibonacci Series in C:
#include<stdio.h>
#include<conio.h>
void main()
{ int n,i,f,f1=0,f2=1; clrscr(); printf(" Enter The Number:"); scanf("%d",&n); printf(" The Fibonacci Series is:"); printf(" n %dn %d",f1,f2); for(i=2;i<n;i++) { f=f1+f2; f1=f2; f2=f; printf(" n %d",f); } getch();
}
Related: Fibonacci Series in C++ using For Loop
Working:
- First the computer reads the value of number of terms for the Fibonacci series from the user.
- Then using for loop the two preceding(previous) numbers are added and printed.
- The loop continues till the value of number of terms.
Step by Step working of the above Program Code:
Let us assume that the Number of Terms entered by the user is 5.
- It assigns the value of n=5 and prints the first two numbers “f1” and “f2” (ie. 0 and 1) on the output screen.
- Then it assigns the value of i=2 in the initialization part of the for loop.
- Then the loop continues till the condition of the for loop is true.
3.1. i<n (2<5), for loop condition is true
f=f1+f2 (f=0+1) So f=1
f1=f2 (f1=1) So f1=1
f2=f (f2=1) So f2=1
print the value of “f” (ie. 1)
i++ (i=i+1) So i=3
3.2. i<n (3<5), for loop condition is true
f=f1+f2 (f=1+1) So f=2
f1=f2 (f1=1) So f1=1
f2=f (f2=2) So f2=2
print the value of “f” (ie. 2)
i++ (i=i+1) So i=4
3.3. i<n (4<5), for loop condition is true
f=f1+f2 (f=1+2) So f=3
f1=f2 (f1=2) So f1=2
f2=f (f2=3) So f2=3
print the value of “f” (ie. 3)
i++ (i=i+1) So i=5
3.4. i<n (5<5), for loop condition is false
comes out of the for loop.
- Thus the program execution is completed.
Output:
