33 lines
1.1 KiB
Rust
33 lines
1.1 KiB
Rust
// 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: ./part1 < input
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pub mod common;
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use common::{Moves, Stacks};
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fn main() -> Result<(), &'static str> {
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let mut stacks = Stacks::from_stdin()?;
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for op in Moves::from_stdin() {
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stacks.move_items(op?)?;
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}
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let result: Result<String, _> = stacks
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.map(|s| s.last().cloned().ok_or("at least one stack is empty"))
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.collect();
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println!("{}", result?);
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Ok(())
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}
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