The Fibonacci sequence is a series where the next term is the sum of the previous two terms. The first two terms of the Fibonacci sequence is **0** followed by **1**.

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

## Example 1: Fibonacci Series up to n number of terms

```
#include <iostream>
using namespace std;
int main() {
int n, t1 = 0, t2 = 1, nextTerm = 0;
cout << "Enter the number of terms: ";
cin >> n;
cout << "Fibonacci Series: ";
for (int i = 1; i <= n; ++i) {
// Prints the first two terms.
if(i == 1) {
cout << t1 << ", ";
continue;
}
if(i == 2) {
cout << t2 << ", ";
continue;
}
nextTerm = t1 + t2;
t1 = t2;
t2 = nextTerm;
cout << nextTerm << ", ";
}
return 0;
}
```

**Output**

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

## Example 2: Program to Generate Fibonacci Sequence Up to a Certain Number

```
#include <iostream>
using namespace std;
int main() {
int t1 = 0, t2 = 1, nextTerm = 0, n;
cout << "Enter a positive number: ";
cin >> n;
// displays the first two terms which is always 0 and 1
cout << "Fibonacci Series: " << t1 << ", " << t2 << ", ";
nextTerm = t1 + t2;
while(nextTerm <= n) {
cout << nextTerm << ", ";
t1 = t2;
t2 = nextTerm;
nextTerm = t1 + t2;
}
return 0;
}
```

**Output**

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