text: /*
  The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1. That is,
  F(0) = 0,   F(1) = 1
  F(N) = F(N - 1) + F(N - 2), for N > 1.
  Given N, calculate F(N).
  
  Runtime: 8 ms, faster than 38.08% of C++ online submissions for Fibonacci Number.
  Memory Usage: 8.1 MB, less than 100.00% of C++ online submissions for Fibonacci Number.
  */
  
  class Solution {
  public:
  	int fib(int N) {
  		if (N == 0) return 0;
  		if (N == 1 || N == 2) return 1;
  
  		return fib(N - 1) + fib(N - 2);
  	}
  };