41 lines
912 B
Rust
41 lines
912 B
Rust
const LOOP_COUNT: i32 = 1_000_000;
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const EXPECTED_CHECKSUM: i32 = 3_875_007;
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fn configured_loop_count() -> i32 {
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let mut input = String::new();
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if std::io::stdin().read_line(&mut input).is_err() {
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return LOOP_COUNT;
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}
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input
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.trim()
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.parse::<i32>()
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.ok()
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.filter(|value| *value > 0)
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.unwrap_or(LOOP_COUNT)
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}
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fn vec_i32_index_loop(limit: i32) -> i32 {
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let digits = vec![3, 1, 4, 1, 5, 9, 2, 6];
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let mut i = 0;
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let mut acc = 7;
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while i < limit {
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acc += digits[(i % digits.len() as i32) as usize];
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acc = if acc > 1_000_000_000 {
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acc - 1_000_000_000
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} else {
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acc
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};
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i += 1;
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}
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acc
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}
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fn main() {
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let result = vec_i32_index_loop(configured_loop_count());
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println!("{}", result);
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std::process::exit(if result == EXPECTED_CHECKSUM { 0 } else { 1 });
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}
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