Jakub Kotur | c72d720 | 2020-12-21 17:28:15 +0100 | [diff] [blame^] | 1 | use std::error::Error; |
| 2 | use std::io; |
| 3 | use std::process; |
| 4 | |
| 5 | use serde::Deserialize; |
| 6 | |
| 7 | #[derive(Debug, Deserialize)] |
| 8 | #[serde(rename_all = "PascalCase")] |
| 9 | struct Record<'a> { |
| 10 | country: &'a [u8], |
| 11 | city: &'a [u8], |
| 12 | accent_city: &'a [u8], |
| 13 | region: &'a [u8], |
| 14 | population: Option<u64>, |
| 15 | latitude: f64, |
| 16 | longitude: f64, |
| 17 | } |
| 18 | |
| 19 | fn run() -> Result<u64, Box<dyn Error>> { |
| 20 | let mut rdr = csv::Reader::from_reader(io::stdin()); |
| 21 | let mut raw_record = csv::ByteRecord::new(); |
| 22 | let headers = rdr.byte_headers()?.clone(); |
| 23 | |
| 24 | let mut count = 0; |
| 25 | while rdr.read_byte_record(&mut raw_record)? { |
| 26 | let record: Record = raw_record.deserialize(Some(&headers))?; |
| 27 | if record.country == b"us" && record.region == b"MA" { |
| 28 | count += 1; |
| 29 | } |
| 30 | } |
| 31 | Ok(count) |
| 32 | } |
| 33 | |
| 34 | fn main() { |
| 35 | match run() { |
| 36 | Ok(count) => { |
| 37 | println!("{}", count); |
| 38 | } |
| 39 | Err(err) => { |
| 40 | println!("{}", err); |
| 41 | process::exit(1); |
| 42 | } |
| 43 | } |
| 44 | } |