Class Solution
java.lang.Object
g1701_1800.s1706_where_will_the_ball_fall.Solution
1706 - Where Will the Ball Fall.<p>Medium</p>
<p>You have a 2-D <code>grid</code> of size <code>m x n</code> representing a box, and you have <code>n</code> balls. The box is open on the top and bottom sides.</p>
<p>Each cell in the box has a diagonal board spanning two corners of the cell that can redirect a ball to the right or to the left.</p>
<ul>
<li>A board that redirects the ball to the right spans the top-left corner to the bottom-right corner and is represented in the grid as <code>1</code>.</li>
<li>A board that redirects the ball to the left spans the top-right corner to the bottom-left corner and is represented in the grid as <code>-1</code>.</li>
</ul>
<p>We drop one ball at the top of each column of the box. Each ball can get stuck in the box or fall out of the bottom. A ball gets stuck if it hits a “V” shaped pattern between two boards or if a board redirects the ball into either wall of the box.</p>
<p>Return <em>an array</em> <code>answer</code> <em>of size</em> <code>n</code> <em>where</em> <code>answer[i]</code> <em>is the column that the ball falls out of at the bottom after dropping the ball from the</em> <code>i<sup>th</sup></code> <em>column at the top, or <code>-1</code> <em>if the ball gets stuck in the box</em>.</em></p>
<p><strong>Example 1:</strong></p>
<p><strong><img src="https://assets.leetcode.com/uploads/2019/09/26/ball.jpg" alt="" /></strong></p>
<p><strong>Input:</strong> grid = [[1,1,1,-1,-1],[1,1,1,-1,-1],[-1,-1,-1,1,1],[1,1,1,1,-1],[-1,-1,-1,-1,-1]]</p>
<p><strong>Output:</strong> [1,-1,-1,-1,-1]</p>
<p><strong>Explanation:</strong> This example is shown in the photo.</p>
<p>Ball b0 is dropped at column 0 and falls out of the box at column 1.</p>
<p>Ball b1 is dropped at column 1 and will get stuck in the box between column 2 and 3 and row 1.</p>
<p>Ball b2 is dropped at column 2 and will get stuck on the box between column 2 and 3 and row 0.</p>
<p>Ball b3 is dropped at column 3 and will get stuck on the box between column 2 and 3 and row 0.</p>
<p>Ball b4 is dropped at column 4 and will get stuck on the box between column 2 and 3 and row 1.</p>
<p><strong>Example 2:</strong></p>
<p><strong>Input:</strong> grid = [[-1]]</p>
<p><strong>Output:</strong> [-1]</p>
<p><strong>Explanation:</strong> The ball gets stuck against the left wall.</p>
<p><strong>Example 3:</strong></p>
<p><strong>Input:</strong> grid = [[1,1,1,1,1,1],[-1,-1,-1,-1,-1,-1],[1,1,1,1,1,1],[-1,-1,-1,-1,-1,-1]]</p>
<p><strong>Output:</strong> [0,1,2,3,4,-1]</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>m == grid.length</code></li>
<li><code>n == grid[i].length</code></li>
<li><code>1 <= m, n <= 100</code></li>
<li><code>grid[i][j]</code> is <code>1</code> or <code>-1</code>.</li>
</ul>
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Constructor Summary
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Method Summary
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Constructor Details
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Solution
public Solution()
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Method Details
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findBall
public int[] findBall(int[][] grid)
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