C program to display the Fibonacci sequence

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In this example, you will learn to display the Fibonacci sequence of the first n numbers (input by the user).

To understand this example, you should understand the followingC programmingTopic:

• C programming operators

• C while and do ... while loops

• C for loop

• C break and continue statements

The Fibonacci sequence is a sequence where the next term is the sum of the previous two terms. The first two terms of the Fibonacci sequence are 0, followed by1.

The Fibonacci sequence: 0,　1,　1,　2,　3,　5,　8,　13,　21

The n-th term of the Fibonacci sequence

#include <stdio.h>
int main() {
　　　　int i, n, t1　= 0, t2　=　1, nextTerm;
　　　　printf("Enter the number of terms: ");
　　　　scanf("%d", &n);
　　　　printf("Fibonacci sequence: ");
　　　　for (i =　1; i <= n;　++i) {
　　　　　　　　printf("%d, ", t1);
　　　　　　　　nextTerm = t1　+　t2;
　　　　　　　　t1　= t2;
　　　　　　　　t2　= nextTerm;
　　　　}
　　　　return 0;
}

Output Result

Enter the number of terms:　10
Fibonacci sequence: 0,　1,　1,　2,　3,　5,　8,　13,　21,　34,

Fibonacci sequence up to a certain number

#include <stdio.h>
int main() {
　　　　int t1　= 0, t2　=　1, nextTerm = 0, n;
　　　　printf("Enter a positive number: ");
　　　　scanf("%d", &n);
　　　　//Display the first two terms, which are always 0 and1
　　　　printf("Fibonacci Series: %d, %d, ", t1, t2);
　　　　nextTerm = t1　+　t2;
　　　　while (nextTerm <= n) {
　　　　　　　　printf("%d, ", nextTerm);
　　　　　　　　t1　= t2;
　　　　　　　　t2　= nextTerm;
　　　　　　　　nextTerm = t1　+　t2;
　　　　}
　　　　return 0;
}

Output Result

Enter a positive integer:　100
Fibonacci Series: 0,　1,　1,　2,　3,　5,　8,　13,　21,　34,　55,　89,

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