// Calculate Fibonacci numbers fn main() { for num in 0..=30 { println("fib(", num, ") = ", fibit(num)) } for num in 0..=30 { println("fib(", num, ") = ", fib(num)) } } /// The classic recursive definition of fib() fn fib(a: i64) -> i64 { if a > 1 { fib(a - 1) + fib(a - 2) } else a } /// The classic iterative algorithm for fib() fn fibit(n: i64) -> i64 { let mut a = 0; let mut b = 1; let mut c = 1; for _ in 0..n { a = b; b = c; c = a + b; } else a }