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use std::collections::HashMap;
use std::io::{self, Read};
fn solve(input: &str) -> (i32, i32) {
let mut max = 0;
let mut regs = HashMap::new();
for line in input.lines() {
let mut words = line.split_whitespace();
let dest = words.next().unwrap();
let op = words.next().unwrap();
let val = words.next().unwrap();
assert_eq!(Some("if"), words.next());
let src = words.next().unwrap();
let cmp = words.next().unwrap();
let rhs = words.next().unwrap();
let mut val: i32 = val.parse().unwrap();
if op == "dec" {
val = -val;
}
let rhs: i32 = rhs.parse().unwrap();
let src = *regs.entry(src.to_owned()).or_insert(0);
let dest = regs.entry(dest.to_owned()).or_insert(0);
let cond = match cmp {
"==" => src == rhs,
"!=" => src != rhs,
"<=" => src <= rhs,
">=" => src >= rhs,
"<" => src < rhs,
">" => src > rhs,
_ => unimplemented!(),
};
if cond {
*dest += val;
}
if *dest > max {
max = *dest;
}
}
(regs.values().cloned().max().unwrap(), max)
}
fn main() {
let mut input = String::new();
io::stdin().read_to_string(&mut input).unwrap();
println!("Part 1: {}", solve(&input).0);
println!("Part 2: {}", solve(&input).1);
}
#[test]
fn part1() {
assert_eq!(1, solve(
"\
b inc 5 if a > 1
a inc 1 if b < 5
c dec -10 if a >= 1
c inc -20 if c == 10
"
).0);
}
#[test]
fn part2() {
assert_eq!(10, solve(
"\
b inc 5 if a > 1
a inc 1 if b < 5
c dec -10 if a >= 1
c inc -20 if c == 10
"
).1);
}
|