43 lines
980 B
Rust
43 lines
980 B
Rust
#![allow(dead_code)]
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use serde::Deserialize;
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use std::{error::Error, io, process};
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#[derive(Debug, Deserialize)]
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#[serde(rename_all = "PascalCase")]
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struct Record<'a> {
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country: &'a str,
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city: &'a str,
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accent_city: &'a str,
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region: &'a str,
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population: Option<u64>,
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latitude: f64,
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longitude: f64,
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}
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fn run() -> Result<u64, Box<dyn Error>> {
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let mut rdr = csv::Reader::from_reader(io::stdin());
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let mut raw_record = csv::StringRecord::new();
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let headers = rdr.headers()?.clone();
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let mut count = 0;
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while rdr.read_record(&mut raw_record)? {
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let record: Record = raw_record.deserialize(Some(&headers))?;
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if record.country == "us" && record.region == "MA" {
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count += 1;
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}
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}
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Ok(count)
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}
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fn main() {
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match run() {
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Ok(count) => {
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println!("{}", count);
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}
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Err(err) => {
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println!("{}", err);
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process::exit(1);
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}
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}
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}
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