Algorithmsbeginner

Fibonacci

📖 Usage Example

function fib(n) {
  return n <= 1 ? n : fib(n - 1) + fib(n - 2);
}
fib(6); // 8

The Fibonacci sequence adds the two previous values; base cases are 0 and 1.

Fibonacci Sequence

The Fibonacci sequence is a series where each number is the sum of the two preceding ones:

0, 1, 1, 2, 3, 5, 8, 13, 21, 34...
fib(0) = 0
fib(1) = 1
fib(n) = fib(n-1) + fib(n-2) for n > 1

This is a classic recursive problem.

function fib(n: number): number {
  // Return the nth Fibonacci number
}

fib(7) // 13
fib(0) // 0

💡 Hints (4)

• Base cases: fib(0) = 0, fib(1) = 1.
• Recursive case: fib(n) = fib(n-1) + fib(n-2).
• Use the ternary operator for conciseness.
• Note: This naive implementation is exponential in time complexity (O(2^n)). For large n, consider memoization.

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