Add problem 1958: Check if Move is Legal

src/lib.rs

@@ -1369,6 +1369,7 @@ pub mod problem_1944_number_of_visible_people_in_a_queue;
 pub mod problem_1945_sum_of_digits_of_string_after_convert;
 pub mod problem_1952_three_divisors;
 pub mod problem_1957_delete_characters_to_make_fancy_string;
+pub mod problem_1958_check_if_move_is_legal;
 pub mod problem_1961_check_if_string_is_a_prefix_of_array;
 pub mod problem_1962_remove_stones_to_minimize_the_total;
 pub mod problem_1963_minimum_number_of_swaps_to_make_the_string_balanced;

src/problem_1958_check_if_move_is_legal/iterative.rs

@@ -0,0 +1,77 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+use std::iter;
+
+impl Solution {
+    fn is_legal(board: &[u8; 64], mut location: (u8, u8), step: (u8, u8), middle: u8, end: u8) -> bool {
+        location = (location.0.wrapping_add(step.0), location.1.wrapping_add(step.1));
+
+        let mut iter = iter::from_fn(|| {
+            (location.0 < 8 && location.1 < 8).then(|| {
+                let result = board[usize::from(location.0 * 8 + location.1)];
+
+                location = (location.0.wrapping_add(step.0), location.1.wrapping_add(step.1));
+
+                result
+            })
+        });
+
+        if iter.next() == Some(middle) {
+            for value in iter {
+                if value == end {
+                    return true;
+                } else if value != middle {
+                    break;
+                }
+            }
+        }
+
+        false
+    }
+
+    pub fn check_move(board: Vec<Vec<char>>, r_move: i32, c_move: i32, color: char) -> bool {
+        let mut board_2 = [0_u8; 64];
+
+        for (target, cell) in board_2.iter_mut().zip(board.into_iter().flatten()) {
+            *target = cell as _;
+        }
+
+        let location = (r_move as _, c_move as _);
+        let (middle, end) = if color == 'B' { (b'W', b'B') } else { (b'B', b'W') };
+
+        for step in [
+            (u8::MAX, u8::MAX),
+            (u8::MAX, 0),
+            (u8::MAX, 1),
+            (0, u8::MAX),
+            (0, 1),
+            (1, u8::MAX),
+            (1, 0),
+            (1, 1),
+        ] {
+            if Self::is_legal(&board_2, location, step, middle, end) {
+                return true;
+            }
+        }
+
+        false
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn check_move(board: Vec<Vec<char>>, r_move: i32, c_move: i32, color: char) -> bool {
+        Self::check_move(board, r_move, c_move, color)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}

src/problem_1958_check_if_move_is_legal/mod.rs

@@ -0,0 +1,49 @@
+pub mod iterative;
+
+pub trait Solution {
+    fn check_move(board: Vec<Vec<char>>, r_move: i32, c_move: i32, color: char) -> bool;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [
+            (
+                (
+                    [
+                        "...B....", "...W....", "...W....", "...W....", "WBB.WWWB", "...B....", "...B....", "...W....",
+                    ],
+                    4,
+                    3,
+                    'B',
+                ),
+                true,
+            ),
+            (
+                (
+                    [
+                        "........", ".B..W...", "..W.....", "...WB...", "........", "....BW..", "......W.", ".......B",
+                    ],
+                    4,
+                    4,
+                    'W',
+                ),
+                false,
+            ),
+        ];
+
+        for ((board, r_move, c_move, color), expected) in test_cases {
+            assert_eq!(
+                S::check_move(
+                    board.iter().map(|row| row.chars().collect()).collect(),
+                    r_move,
+                    c_move,
+                    color,
+                ),
+                expected,
+            );
+        }
+    }
+}