交互读取数字

fn main(){    let mut index = String::new();    use std::io;    io::stdin().read_line(&mut index).expect("not a num");    let trimmed = index.trim();    match trimmed.parse::
    
     () {        Ok(i) => println!("input:{}",i),        Err(..) => println!("this was not an integer: {}", trimmed),    }}
    

启动时传入参数

fn main(){    use std::env;    let args: Vec
    
      = env::args().collect();    assert!(args.len()>1);//断言传入参数    match args[1].parse::
     
      () {        Ok(num) => println!("output:{}",num),        Err(..) => println!("this was not an integer: {}",args[1]),    }       }
     
    

ps:以上代码原型来自与https://doc.rust-lang.org及stackoverflow