aloalgoFibonacci Number
Easy
You are given an integer n.
Your task is to calculate the n-th Fibonacci number, denoted F(n).
Remember that:
- The Fibonacci sequence is a series of numbers in which each number is the sum of the two preceding ones.
- The sequence is defined by the recurrence relation
F(n) = F(n - 1) + F(n - 2). - The base cases are
F(0) = 0andF(1) = 1.
Return the n-th Fibonacci number.
Example 1
Input
2
Output
1
Explanation:
F(2) = F(1) + F(0) = 1 + 0 = 1.
Example 2
Input
3
Output
2
Explanation:
F(3) = F(2) + F(1) = 1 + 1 = 2.
Example 3
Input
4
Output
3
Explanation:
F(4) = F(3) + F(2) = 2 + 1 = 3.
Input
2
Output
1