1/// 将给定的数字加一 2/// 3/// # Examples 4/// 5/// ``` 6/// let arg = 5; 7/// let answer = lib_test::add_one(arg); 8/// 9/// assert_eq!(6, answer); 10/// ``` 11pub fn add_one(x: i32) -> i32 { 12 x + 1 13}