The code, written in Rust, solve the Days in Month problem in CodeChef. Also my first few program written in Rust.

https://www.codechef.com/problems/NW1

The code is accepted so that there is no logical mistakes. I am more interested in getting review feedback on style. I am not particularly happy with the code as is, it is rather bulky.

use std::io;  fn read_line(stdin: &io::Stdin) -> io::Result<String> {     let mut input = String::new();     match stdin.read_line(&mut input)     {         Ok(_) => Ok(input.trim().to_string()),         Err(e) => Err(e)     } }  fn to_day_of_week(input: &str) -> Option<usize> {     if input == "mon"     {         Some(0)     }     else if input == "tues"     {         Some(1)     }     else if input == "wed"     {         Some(2)     }     else if input == "thurs"     {         Some(3)     }     else if input == "fri"     {         Some(4)     }     else if input == "sat"     {         Some(5)     }     else if input == "sun"     {         Some(6)     }     else     {          None     } }  pub fn codechef_nw1() {     let stdin = io::stdin();     let read_first_line_result = read_line(&stdin);     if read_first_line_result.is_ok()     {         let first_line = read_first_line_result.unwrap();         let parse_first_line_result = first_line.parse::<i32>();         if parse_first_line_result.is_ok()         {             let t = parse_first_line_result.unwrap();             for _i in 0..t             {                 let read_test_line_result = read_line(&stdin);                 if read_test_line_result.is_ok()                 {                     let test_line = read_test_line_result.unwrap();                     let find_space_result = test_line.find(' ');                     if find_space_result.is_some()                     {                         let space_index = find_space_result.unwrap();                         let test_token_1 = &test_line[..space_index];                         let test_token_2 = &test_line[space_index + 1..];                         let parse_day_result = test_token_1.parse::<i32>();                         if parse_day_result.is_ok()                         {                             let days = parse_day_result.unwrap();                             let day_of_week_result = to_day_of_week(test_token_2);                             if day_of_week_result.is_some()                             {                                 let mut day_of_week = day_of_week_result.unwrap();                                 let mut stats = [0, 0, 0, 0, 0, 0, 0];                                 for _d in 0..days                                 {                                     stats[day_of_week] = stats[day_of_week] + 1;                                     day_of_week = day_of_week + 1;                                     day_of_week = day_of_week % 7;                                 }                                 println!("{} {} {} {} {} {} {}", stats[0], stats[1], stats[2], stats[3], stats[4], stats[5], stats[6]);                             }                                                     }                     }                 }             }         }     } }