Advent Of Code Day 6

aoc_day_6.rs

struct Mem {
  mem : Vec<i32>
}

impl Mem {
  pub fn new(mem : &Vec<i32>) -> Mem {
    Mem {
      mem : mem.clone()
    }
  }
  
  pub fn mem(&self) -> &Vec<i32> {
    &self.mem
  }
  
  pub fn highest_bank(&self) -> usize {
    let mut index = 0;
    let mut max   = 0;
    for (i, &bank) in self.mem.iter().enumerate().rev() {
      if bank >= max {
        max = bank;
        index = i;
      }
    }
    index
  }
  
  pub fn redistribute(&mut self) {
    let mut idx = self.highest_bank();
    let mut val = self.mem[idx];
    self.mem[idx] = 0;
    while val > 0 {
      val -= 1;
      idx = (idx + 1) % self.mem.len();
      self.mem[idx] += 1;
    }
  }
  
  pub fn show(&self) {
    println!("{:?}", self.mem);
  }
}

fn main() {
  let test_data = vec![0, 2, 7, 0];
  let prod_data = vec![10, 3, 15, 10, 5, 15, 5, 15, 9, 2, 5, 8, 5, 2, 3, 6];
  let mut mem = Mem::new(&prod_data);
  mem.show();
  
  let mut cycle = 0;
  let mut banks = Vec::<Vec<i32>>::new();
  loop {
    cycle += 1;
    mem.redistribute();
    mem.show();
    let curr_mem = mem.mem();
    if banks.contains(&curr_mem) {
      break;
    }
    banks.push(curr_mem.clone());
  }
  
  let mut cycle_2 = 0;
  let first = mem.mem().clone();
  loop {
    cycle_2 += 1;
    mem.redistribute();
    mem.show();
    if &first == mem.mem() {
      break;
    }
  }
  
  println!("cycles  : {}", cycle);
  println!("cycles 2: {}", cycle_2);
}