{ "data": { "question": { "questionId": "62", "questionFrontendId": "62", "boundTopicId": null, "title": "Unique Paths", "titleSlug": "unique-paths", "content": "

There is a robot on an m x n grid. The robot is initially located at the top-left corner (i.e., grid[0][0]). The robot tries to move to the bottom-right corner (i.e., grid[m - 1][n - 1]). The robot can only move either down or right at any point in time.

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Given the two integers m and n, return the number of possible unique paths that the robot can take to reach the bottom-right corner.

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The test cases are generated so that the answer will be less than or equal to 2 * 109.

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Example 1:

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\nInput: m = 3, n = 7\nOutput: 28\n
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Example 2:

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\nInput: m = 3, n = 2\nOutput: 3\nExplanation: From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:\n1. Right -> Down -> Down\n2. Down -> Down -> Right\n3. Down -> Right -> Down\n
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Constraints:

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