gorb

utils/lib.rs

@@ -0,0 +1,49 @@
+pub trait Matrix {
+    fn transpose(self) -> Self;
+    fn reverse_rows(self) -> Self;
+    fn rotate_counter_clockwise(self) -> Self;
+}
+
+impl<T: Clone> Matrix for Vec<Vec<T>> {
+    // Yes, very inefficient
+    // Easy peasy when
+    fn transpose(self) -> Self {
+        let mut o: Vec<Vec<Option<T>>> = vec![vec![None; self.len()]; self.first().unwrap().len()];
+        self.into_iter().enumerate().for_each(|(y, l)| {
+            l.into_iter().enumerate().for_each(|(x, e)| {
+                o[x][y] = Some(e);
+            })
+        });
+        o.into_iter()
+            .map(|r| r.into_iter().map(|e| e.unwrap()).collect())
+            .collect()
+    }
+
+    fn reverse_rows(self) -> Self {
+        let mut o = self.clone();
+        o.reverse();
+        o
+    }
+
+    fn rotate_counter_clockwise(self) -> Self {
+        self.transpose().reverse_rows()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_transpose() {
+        let x = vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]];
+        let result = vec![vec![1, 4, 7], vec![2, 5, 8], vec![3, 6, 9]];
+        assert_eq!(x.transpose(), result);
+    }
+
+    #[test]
+    fn test_rotate_counter_clockwise() {
+        let x = vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]];
+        let result = vec![vec![3, 6, 9], vec![2, 5, 8], vec![1, 4, 7]];
+        assert_eq!(x.rotate_counter_clockwise(), result);
+    }
+}