divide repository in src and lib

2022-08-14 21:14:01 +02:00
parent 4bac3290e5
commit a43cdc4494
19 changed files with 41 additions and 10 deletions
@@ -0,0 +1,105 @@
+pub struct PositionCombinations {
+    min_length: usize,
+    max_length: usize,
+    state: Vec<bool>,
+    finished: bool,
+}
+
+impl Iterator for PositionCombinations {
+    type Item = Vec<bool>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        loop {
+            let result = self.state.clone();
+            self.increment();
+            if self.finished {
+                return None;
+            }
+            if (self.min_length..=self.max_length).contains(&result.iter().filter(|x| **x).count())
+            {
+                return Some(result);
+            }
+        }
+    }
+}
+
+impl PositionCombinations {
+    pub fn new(min_length: usize, max_length: usize, length: usize) -> Self {
+        let state = vec![false; length];
+        let finished = false;
+        Self {
+            min_length,
+            max_length,
+            state,
+            finished,
+        }
+    }
+
+    fn increment(&mut self) {
+        let mut overflow = self.state[0];
+        self.state[0] ^= true;
+        for position in self.state[1..].iter_mut() {
+            let new_overflow = *position & overflow;
+            *position ^= overflow;
+            overflow = new_overflow;
+        }
+        if overflow {
+            self.finished = true;
+        }
+    }
+}
+
+pub trait ToString {
+    fn to_string(&self) -> String;
+}
+
+impl ToString for Vec<bool> {
+    fn to_string(&self) -> String {
+        self.iter().map(|b| if *b { 'x' } else { '.' }).collect()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::combination::PositionCombinations;
+    use std::collections::HashSet;
+
+    #[test]
+    fn test_combination_2_3_4() {
+        let combinator = PositionCombinations::new(2, 3, 4);
+        let result: Vec<_> = combinator.into_iter().collect();
+        let mut number_solutions = result.len();
+        let mut solution = HashSet::new();
+        solution.insert(vec![false, false, true, true]);
+        solution.insert(vec![false, true, false, true]);
+        solution.insert(vec![false, true, true, false]);
+        solution.insert(vec![false, true, true, true]);
+        solution.insert(vec![true, true, false, false]);
+        solution.insert(vec![true, false, true, false]);
+        solution.insert(vec![true, false, false, true]);
+        solution.insert(vec![true, false, true, true]);
+        solution.insert(vec![true, true, false, true]);
+        solution.insert(vec![true, true, true, false]);
+        for item in solution {
+            assert!(result.contains(&item));
+            number_solutions -= 1;
+        }
+        assert_eq!(number_solutions, 0);
+    }
+
+    #[test]
+    fn test_combination_2_2_3() {
+        let combinator = PositionCombinations::new(2, 2, 3);
+        let result: Vec<_> = combinator.into_iter().collect();
+        let mut number_solutions = result.len();
+        let mut solution = HashSet::new();
+        solution.insert(vec![false, true, true]);
+        solution.insert(vec![true, false, true]);
+        solution.insert(vec![true, true, false]);
+        for item in solution {
+            assert!(result.contains(&item));
+            number_solutions -= 1;
+        }
+        assert_eq!(number_solutions, 0);
+    }
+}