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52 lines
2.5 KiB
HTML
52 lines
2.5 KiB
HTML
<p>You are given an <code>m x n</code> <code>grid</code>. Each cell of <code>grid</code> represents a street. The street of <code>grid[i][j]</code> can be:</p>
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<ul>
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<li><code>1</code> which means a street connecting the left cell and the right cell.</li>
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<li><code>2</code> which means a street connecting the upper cell and the lower cell.</li>
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<li><code>3</code> which means a street connecting the left cell and the lower cell.</li>
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<li><code>4</code> which means a street connecting the right cell and the lower cell.</li>
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<li><code>5</code> which means a street connecting the left cell and the upper cell.</li>
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<li><code>6</code> which means a street connecting the right cell and the upper cell.</li>
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</ul>
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<img alt="" src="https://assets.leetcode.com/uploads/2020/03/05/main.png" style="width: 450px; height: 708px;" />
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<p>You will initially start at the street of the upper-left cell <code>(0, 0)</code>. A valid path in the grid is a path that starts from the upper left cell <code>(0, 0)</code> and ends at the bottom-right cell <code>(m - 1, n - 1)</code>. <strong>The path should only follow the streets</strong>.</p>
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<p><strong>Notice</strong> that you are <strong>not allowed</strong> to change any street.</p>
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<p>Return <code>true</code><em> if there is a valid path in the grid or </em><code>false</code><em> otherwise</em>.</p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<img alt="" src="https://assets.leetcode.com/uploads/2020/03/05/e1.png" style="width: 455px; height: 311px;" />
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<pre>
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<strong>Input:</strong> grid = [[2,4,3],[6,5,2]]
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<strong>Output:</strong> true
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<strong>Explanation:</strong> As shown you can start at cell (0, 0) and visit all the cells of the grid to reach (m - 1, n - 1).
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</pre>
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<p><strong>Example 2:</strong></p>
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<img alt="" src="https://assets.leetcode.com/uploads/2020/03/05/e2.png" style="width: 455px; height: 293px;" />
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<pre>
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<strong>Input:</strong> grid = [[1,2,1],[1,2,1]]
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<strong>Output:</strong> false
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<strong>Explanation:</strong> As shown you the street at cell (0, 0) is not connected with any street of any other cell and you will get stuck at cell (0, 0)
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</pre>
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<p><strong>Example 3:</strong></p>
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<pre>
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<strong>Input:</strong> grid = [[1,1,2]]
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<strong>Output:</strong> false
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<strong>Explanation:</strong> You will get stuck at cell (0, 1) and you cannot reach cell (0, 2).
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</pre>
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<p> </p>
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<p><strong>Constraints:</strong></p>
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<ul>
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<li><code>m == grid.length</code></li>
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<li><code>n == grid[i].length</code></li>
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<li><code>1 <= m, n <= 300</code></li>
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<li><code>1 <= grid[i][j] <= 6</code></li>
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</ul>
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