<p>In an&nbsp;<code>n*n</code>&nbsp;grid, there is a snake that spans 2 cells and starts moving from the top left corner at <code>(0, 0)</code> and <code>(0, 1)</code>. The grid has empty cells represented by zeros and blocked cells represented by ones. The snake wants to reach the lower right corner at&nbsp;<code>(n-1, n-2)</code>&nbsp;and&nbsp;<code>(n-1, n-1)</code>.</p>

<p>In one move the snake can:</p>

<ul>
	<li>Move one cell to the right&nbsp;if there are no blocked cells there. This move keeps the horizontal/vertical position of the snake as it is.</li>
	<li>Move down one cell&nbsp;if there are no blocked cells there. This move keeps the horizontal/vertical position of the snake as it is.</li>
	<li>Rotate clockwise if it&#39;s in a horizontal position and the two cells under it are both empty. In that case the snake moves from&nbsp;<code>(r, c)</code>&nbsp;and&nbsp;<code>(r, c+1)</code>&nbsp;to&nbsp;<code>(r, c)</code>&nbsp;and&nbsp;<code>(r+1, c)</code>.<br />
	<img alt="" src="https://assets.leetcode.com/uploads/2019/09/24/image-2.png" style="width: 300px; height: 134px;" /></li>
	<li>Rotate counterclockwise&nbsp;if it&#39;s in a vertical position and the two cells to its right are both empty. In that case the snake moves from&nbsp;<code>(r, c)</code>&nbsp;and&nbsp;<code>(r+1, c)</code>&nbsp;to&nbsp;<code>(r, c)</code>&nbsp;and&nbsp;<code>(r, c+1)</code>.<br />
	<img alt="" src="https://assets.leetcode.com/uploads/2019/09/24/image-1.png" style="width: 300px; height: 121px;" /></li>
</ul>

<p>Return the minimum number of moves to reach the target.</p>

<p>If there is no way to reach the target, return&nbsp;<code>-1</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2019/09/24/image.png" style="width: 400px; height: 439px;" /></strong></p>

<pre>
<strong>Input:</strong> grid = [[0,0,0,0,0,1],
               [1,1,0,0,1,0],
&nbsp;              [0,0,0,0,1,1],
&nbsp;              [0,0,1,0,1,0],
&nbsp;              [0,1,1,0,0,0],
&nbsp;              [0,1,1,0,0,0]]
<strong>Output:</strong> 11
<strong>Explanation:
</strong>One possible solution is [right, right, rotate clockwise, right, down, down, down, down, rotate counterclockwise, right, down].
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> grid = [[0,0,1,1,1,1],
&nbsp;              [0,0,0,0,1,1],
&nbsp;              [1,1,0,0,0,1],
&nbsp;              [1,1,1,0,0,1],
&nbsp;              [1,1,1,0,0,1],
&nbsp;              [1,1,1,0,0,0]]
<strong>Output:</strong> 9
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>2 &lt;= n &lt;= 100</code></li>
	<li><code>0 &lt;= grid[i][j] &lt;= 1</code></li>
	<li>It is guaranteed that the snake starts at empty cells.</li>
</ul>

class Solution {
public:
    int minimumMoves(vector<vector<int>>& grid) {
        int n = grid.size();
        queue<tuple<int, int, int>> q; // (row, col, isHorizontal)
        set<tuple<int, int, int>> visited; // track visited states
        q.push({0, 0, 1}); // Start from the top-left corner in horizontal position
        visited.insert({0, 0, 1});
        int moves = 0;

        while (!q.empty()) {
            int size = q.size();
            for (int i = 0; i < size; i++) {
                auto [r, c, isHorizontal] = q.front();
                q.pop();

                // Check if the snake has reached the target position
                if (r == n - 1 && c == n - 2 && isHorizontal == 1) {
                    return moves;
                }

                // Move right
                if (isHorizontal && c + 2 < n && grid[r][c + 2] == 0 && visited.count({r, c + 1, 1}) == 0) {
                    q.push({r, c + 1, 1});
                    visited.insert({r, c + 1, 1});
                }

                // Move down
                if (!isHorizontal && r + 2 < n && grid[r + 2][c] == 0 && visited.count({r + 1, c, 0}) == 0) {
                    q.push({r + 1, c, 0});
                    visited.insert({r + 1, c, 0});
                }

                // Rotate clockwise from horizontal to vertical
                if (isHorizontal && r + 1 < n && grid[r + 1][c] == 0 && grid[r + 1][c + 1] == 0 && visited.count({r, c, 0}) == 0) {
                    q.push({r, c, 0});
                    visited.insert({r, c, 0});
                }

                // Rotate counterclockwise from vertical to horizontal
                if (!isHorizontal && c + 1 < n && grid[r][c + 1] == 0 && grid[r + 1][c + 1] == 0 && visited.count({r, c, 1}) == 0) {
                    q.push({r, c, 1});
                    visited.insert({r, c, 1});
                }

                // Move down if horizontal
                if (isHorizontal && r + 1 < n && grid[r + 1][c] == 0 && grid[r + 1][c + 1] == 0 && visited.count({r + 1, c, 1}) == 0) {
                    q.push({r + 1, c, 1});
                    visited.insert({r + 1, c, 1});
                }

                // Move right if vertical
                if (!isHorizontal && c + 1 < n && grid[r][c + 1] == 0 && grid[r + 1][c + 1] == 0 && visited.count({r, c + 1, 0}) == 0) {
                    q.push({r, c + 1, 0});
                    visited.insert({r, c + 1, 0});
                }
            }
            moves++;
        }
        return -1; // If no path found
    }
};
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