Rust – Fibonacci using Recursion and Iteration

Rust – Fibonacci using Recursion and Iteration

 

use std::time::{Duration, Instant, SystemTime};

fn fibonacci_recusive(n: i64) -> i64 {
    if n < 2 {
        return n;
    }
    return fibonacci_recusive(n - 1) + fibonacci_recusive(n - 2);
}

fn fibonacci_iterative(n: i64) -> i64 {
    let mut first_number: i64 = 0;
    let mut second_number: i64 = 0;
    let mut current_number: i64 = 1;

    let mut i: i64 = 1;

    while i < n {
        first_number = second_number;

        second_number = current_number;

        current_number = first_number + second_number;

        i = i + 1;
    }
    current_number
}

fn main() {
    let start_sys_time_recursive = Instant::now();
    println!("{}", fibonacci_recusive(50));
    println!(
        "Recursive {:?}",
        start_sys_time_recursive.elapsed().as_millis()
    );

    let start_sys_time_iterative = Instant::now();

    println!("{}", fibonacci_iterative(50));
    println!(
        "Recursive {:?}",
        start_sys_time_iterative.elapsed().as_millis()
    );
}

 

 

https://turreta.com/2019/10/05/rust-fibonacci-using-recursion-and-iteration/

Rust - Fibonacci using Recursion and Iteration

 

 

 

 

 

 

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