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            "content": "<p>Given an integer array <code>arr</code>, and an integer <code>target</code>, return the number of tuples <code>i, j, k</code> such that <code>i &lt; j &lt; k</code> and <code>arr[i] + arr[j] + arr[k] == target</code>.</p>\n\n<p>As the answer can be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> arr = [1,1,2,2,3,3,4,4,5,5], target = 8\n<strong>Output:</strong> 20\n<strong>Explanation: </strong>\nEnumerating by the values (arr[i], arr[j], arr[k]):\n(1, 2, 5) occurs 8 times;\n(1, 3, 4) occurs 8 times;\n(2, 2, 4) occurs 2 times;\n(2, 3, 3) occurs 2 times.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> arr = [1,1,2,2,2,2], target = 5\n<strong>Output:</strong> 12\n<strong>Explanation: </strong>\narr[i] = 1, arr[j] = arr[k] = 2 occurs 12 times:\nWe choose one 1 from [1,1] in 2 ways,\nand two 2s from [2,2,2,2] in 6 ways.\n</pre>\n\n<p><strong>Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> arr = [2,1,3], target = 6\n<strong>Output:</strong> 1\n<strong>Explanation:</strong> (1, 2, 3) occured one time in the array so we return 1.\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>3 &lt;= arr.length &lt;= 3000</code></li>\n\t<li><code>0 &lt;= arr[i] &lt;= 100</code></li>\n\t<li><code>0 &lt;= target &lt;= 300</code></li>\n</ul>\n",
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