Add moves_to_chessboard

Author: martwz

src/leetcode/challenge/mod.rs

@@ -3,6 +3,7 @@ mod find_max_consecutive_ones;
 mod intersect;
 mod max_length;
 mod minmax_gas_dist;
+mod moves_to_chessboard;
 mod num_distinct;
 mod shortest_distance;
 mod shortest_path;

src/leetcode/challenge/moves_to_chessboard.rs

@@ -0,0 +1,71 @@
+impl Solution {
+    pub fn moves_to_chessboard(board: Vec<Vec<i32>>) -> i32 {
+        let n = board.len();
+
+        for i in 0..n {
+            for j in 0..n {
+                if board[0][0] ^ board[i][0] ^ board[0][j] ^ board[i][j] == 1 {
+                    return -1;
+                }
+            }
+        }
+
+        let [mut row_sum, mut col_sum, mut row_misplaced, mut col_misplaced] = [0, 0, 0, 0];
+        for i in 0..n {
+            row_sum += board[0][i];
+            col_sum += board[i][0];
+
+            if board[i][0] == i as i32 % 2 {
+                row_misplaced += 1;
+            }
+            if board[0][i] == i as i32 % 2 {
+                col_misplaced += 1;
+            }
+        }
+
+        let n = n as i32;
+        if row_sum != n / 2 && row_sum != (n + 1) / 2 {
+            return -1;
+        }
+        if col_sum != n / 2 && col_sum != (n + 1) / 2 {
+            return -1;
+        }
+
+        if n % 2 == 1 {
+            if col_misplaced % 2 == 1 {
+                col_misplaced = n - col_misplaced;
+            }
+            if row_misplaced % 2 == 1 {
+                row_misplaced = n - row_misplaced;
+            }
+        } else {
+            col_misplaced = i32::min(n - col_misplaced, col_misplaced);
+            row_misplaced = i32::min(n - row_misplaced, row_misplaced);
+        }
+
+        (col_misplaced + row_misplaced) / 2
+    }
+}
+
+struct Solution {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::vec_vec_i32;
+
+    #[test]
+    fn test_moves_to_chessboard() {
+        assert_eq!(Solution::moves_to_chessboard(vec_vec_i32![[0, 1, 1, 0], [0, 1, 1, 0], [1, 0, 0, 1], [1, 0, 0, 1]]), 2);
+    }
+
+    #[test]
+    fn test_moves_to_chessboard2() {
+        assert_eq!(Solution::moves_to_chessboard(vec_vec_i32![[0, 1], [1, 0]]), 0);
+    }
+
+    #[test]
+    fn test_moves_to_chessboard3() {
+        assert_eq!(Solution::moves_to_chessboard(vec_vec_i32![[1, 0], [1, 0]]), -1);
+    }
+}