20240621 Finished

src/problem/mod.rs

@@ -154,4 +154,5 @@ mod p637_average_of_levels_in_binary_tree;
 mod p530_minimum_absolute_difference_in_bst;
 mod p230_kth_smallest_element_in_a_bst;
 mod p98_validate_binary_search_tree;
-mod p200_number_of_islands;
+mod p200_number_of_islands;
+mod p130_surrounded_regions;

src/problem/p130_surrounded_regions.rs

@@ -0,0 +1,74 @@
+/**
+ * [130] Surrounded Regions
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+
+impl Solution {
+    fn dfs(board: &mut Vec<Vec<char>>, x: i32, y: i32, m: i32, n: i32) {
+        if x < 0 || x >= m || y < 0 || y >= n {
+            return;
+        }
+
+        let (pos_x, pos_y) = (x as usize, y as usize);
+
+        if board[pos_x][pos_y] != 'O' {
+            return;
+        }
+
+        board[pos_x][pos_y] = 'A';
+
+        Self::dfs(board, x - 1, y, m, n);
+        Self::dfs(board, x + 1, y, m, n);
+        Self::dfs(board, x, y - 1, m, n);
+        Self::dfs(board, x, y + 1, m, n);
+    }
+
+    pub fn solve(board: &mut Vec<Vec<char>>) {
+        let m = board.len();
+        let n = board[0].len();
+        let (m_length, n_length) = (m as i32, n as i32);
+
+        for i in 0..m {
+            if board[i][0] == 'O' {
+                Self::dfs(board, i as i32, 0, m_length, n_length);
+            }
+            if board[i][n - 1] == 'O' {
+                Self::dfs(board, i as i32, n_length - 1, m_length, n_length);
+            }
+        }
+
+        for i in 0..n {
+            if board[0][i] == 'O' {
+                Self::dfs(board, 0, i as i32, m_length, n_length);
+            }
+            if board[m - 1][i] == 'O' {
+                Self::dfs(board, m_length - 1, i as i32, m_length, n_length);
+            }
+        }
+
+        for i in 0..m {
+            for j in 0..n {
+                if board[i][j] == 'O' {
+                    board[i][j] = 'X';
+                }
+                if board[i][j] == 'A' {
+                    board[i][j] = 'O';
+                }
+            }
+        }
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_130() {
+    }
+}