Let's build a Dynamic Calculator! 📟

use k_board::{Keyboard, Keys}; use std::io; fn main() { let mut result: f64 = 0.0; let first: f64 = get_number("first"); let second: f64 = get_number("second"); let operation: i8 = get_operation(); match operation { 0 => result = first + second, 1 => result = first - second, 2 => result = first * second, 3 => { if second != 0.0 { result = first / second } } _ => {} } println!("The result is: {}", result); } fn get_number(position: &str) -> f64 { let mut input: String = String::new(); println!("Enter the {} number: ", position); io::stdin().read_line(&mut input).expect("Error"); let number: f64 = match input.trim().parse() { Ok(number) => number, Err(_) => get_number(position), }; number } fn get_operation() -> i8 { let mut operation: i8 = 0; menu(&mut operation, 0); for key in Keyboard::new() { match key { Keys::Up => menu(&mut operation, -1), Keys::Down => menu(&mut operation, 1), Keys::Enter => break, _ => {} } } operation } fn menu(operation: &mut i8, selection: i8) { std::process::Command::new("clear").status().unwrap(); if *operation > 0 || *operation < 3 { *operation += selection; } let mut op = vec![' ', ' ', ' ', ' ']; for i in 0..4 { if i == *operation { op[i as usize] = '*'; } } println!( "{} Add\n{} Subtract\n{} Multiply\n{} Divide", op[0], op[1], op[2], op[3] ); }