50 lines
1.6 KiB
Rust
50 lines
1.6 KiB
Rust
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// Copyright 2022 Christian Ulrich
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//
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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//
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// usage: ./part2 < input
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pub mod common;
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use common::{FileSystem, Node};
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const DISK_SIZE: usize = 70000000;
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const SPACE_REQUIRED: usize = 30000000;
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fn main() -> Result<(), &'static str> {
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let fs = FileSystem::from_stdin()?;
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let total_size = fs.root().size();
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let free_space = DISK_SIZE - total_size;
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if free_space >= SPACE_REQUIRED {
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return Err("Sufficient free space, nothing to be done!");
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}
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// we need to find a directory of at least this size
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let min_directory_size = SPACE_REQUIRED - free_space;
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let mut result = total_size;
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for node in fs.root().walk() {
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if let Node::Directory {
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name: _,
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children: _,
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} = node
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{
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let size = node.size();
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if size >= min_directory_size && size < result {
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result = size;
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}
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}
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}
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println!("{result}");
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Ok(())
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}
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