Write a program to print the Fibonacci series using a loop. Explain the logic used. - Students Free Notes

Write a program to print the Fibonacci series using a loop. Explain the logic used.

The Fibonacci series is a sequence where each number is the sum of the two preceding ones, starting from 0 and 1. The first few numbers in the Fibonacci sequence are 0, 1, 1, 2, 3, 5, 8, 13, 21,....

Program to print Fibonacci series:

#include <stdio.h>

int main() {
int n, first = 0, second = 1, next;

printf(“Enter the number of terms: “);
scanf(“%d”, &n);

printf(“Fibonacci Series: “);

for(int i = 0; i < n; i++) {
if(i <= 1)
next = i; // First two numbers are 0 and 1
else {
next = first + second; // Next number is the sum of the previous two
first = second; // Update the first number
second = next; // Update the second number
}
printf(“%d “, next);
}

return 0;
}

Logic Explanation:

  • Initialize the first two numbers of the Fibonacci sequence: first = 0, second = 1.
  • Start a loop from i = 0 to n-1.
  • If i is less than or equal to 1, print i (since the first two numbers are 0 and 1).
  • For i > 1, calculate the next Fibonacci number as first + second. Then, update the values of first and second for the next iteration.
  • The loop terminates when n terms are printed.

Example Output:

Enter the number of terms: 7
Fibonacci Series: 0 1 1 2 3 5 8