Solution for prime time (set 1+2)

main
Inga 🏳‍🌈 3 years ago
parent 5555907e0a
commit dec5280700
  1. 9
      0410-1A/task2-primetime/Cargo.toml
  2. 87
      0410-1A/task2-primetime/src/main.rs

@ -0,0 +1,9 @@
[package]
name = "task2-primetime"
version = "0.1.0"
authors = ["inga-lovinde <52715130+inga-lovinde@users.noreply.github.com>"]
edition = "2018"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]

@ -0,0 +1,87 @@
use std::collections::HashMap;
use std::{io::{self, BufRead}};
const PRIMES: [u16; 95] = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499];
fn factorize(mut number: u16) -> Option<HashMap<u16, u16>> {
let mut result = HashMap::new();
for &prime in &PRIMES {
let mut count = 0;
while (number % prime) == 0 {
count += 1;
number = number / prime;
}
if count > 0 {
result.insert(prime, count);
}
}
if number == 1 {
return Some(result);
} else {
return None;
}
}
fn factorize_all() -> HashMap<u16, HashMap<u16, u16>> {
let mut result = HashMap::new();
for i in 1..u16::MAX {
match factorize(i) {
Some(factors) => {
result.insert(i, factors);
},
None => {}
}
}
result
}
fn solve(cards: &Vec<(u16, u16)>, precomputed: &HashMap<u16, HashMap<u16, u16>>) -> Option<u16> {
let sum: u16 = cards.iter().map(|&(prime, count)| prime * count).sum();
let cards_hash = cards.iter().map(|&tuple| tuple.clone()).collect::<HashMap<_, _>>();
for i in (1..=sum).rev() {
match precomputed.get(&i) {
Some(factors) => {
let factors_sum: u16 = factors.iter().map(|(&factor, &count)| factor * count).sum();
if i + factors_sum == sum {
if factors.iter().all(|(&factor, &count)| match cards_hash.get(&factor) {
Some(&original_count) => original_count >= count,
None => false,
}) {
return Some(i);
}
}
}
None => {
}
}
}
return None;
}
fn main() {
let precomputed = factorize_all();
let stdin = io::stdin();
let mut lines = stdin.lock().lines();
let test_number: u32 = lines.next().unwrap().unwrap().parse().unwrap();
for t in 1..=test_number {
let length: u32 = lines.next().unwrap().unwrap().parse().unwrap();
let mut list: Vec<(u16, u16)> = vec![];
for _i in 0..length {
let parts: Vec<u16> = lines.next().unwrap().unwrap().split(char::is_whitespace).map(|part| part.parse().unwrap()).collect();
list.push((parts[0], parts[1]))
}
println!("Case #{}: {}", t, match solve(&list, &precomputed) {
Some(score) => score,
None => 0,
});
}
}
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