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use std::io::{self, Read};
fn solve(input: &str, skip: usize) -> u32 {
let mut sum = 0;
let chars = input.chars();
let nexts = input.chars().cycle().skip(skip);
for (a, b) in chars.zip(nexts) {
if a == b {
sum += a.to_digit(10).unwrap();
}
}
sum
}
fn solve2(input: &str) -> u32 {
solve(input, input.len() / 2)
}
fn main() {
let mut input = String::new();
io::stdin().read_to_string(&mut input).unwrap();
println!("Part 1: {}", solve(input.trim(), 1));
println!("Part 2: {}", solve2(input.trim()));
}
#[test]
fn part1() {
assert_eq!(3, solve("1122", 1));
assert_eq!(4, solve("1111", 1));
assert_eq!(0, solve("1234", 1));
assert_eq!(9, solve("91212129", 1));
}
#[test]
fn part2() {
assert_eq!(6, solve2("1212"));
assert_eq!(0, solve2("1221"));
assert_eq!(4, solve2("123425"));
assert_eq!(12, solve2("123123"));
assert_eq!(4, solve2("12131415"));
}
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