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"title": "Count Substrings That Differ by One Character",
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"content": "<p>Given two strings <code>s</code> and <code>t</code>, find the number of ways you can choose a non-empty substring of <code>s</code> and replace a <strong>single character</strong> by a different character such that the resulting substring is a substring of <code>t</code>. In other words, find the number of substrings in <code>s</code> that differ from some substring in <code>t</code> by <strong>exactly</strong> one character.</p>\n\n<p>For example, the underlined substrings in <code>"<u>compute</u>r"</code> and <code>"<u>computa</u>tion"</code> only differ by the <code>'e'</code>/<code>'a'</code>, so this is a valid way.</p>\n\n<p>Return <em>the number of substrings that satisfy the condition above.</em></p>\n\n<p>A <strong>substring</strong> is a contiguous sequence of characters within a string.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> s = "aba", t = "baba"\n<strong>Output:</strong> 6\n<strong>Explanation:</strong> The following are the pairs of substrings from s and t that differ by exactly 1 character:\n("<u>a</u>ba", "<u>b</u>aba")\n("<u>a</u>ba", "ba<u>b</u>a")\n("ab<u>a</u>", "<u>b</u>aba")\n("ab<u>a</u>", "ba<u>b</u>a")\n("a<u>b</u>a", "b<u>a</u>ba")\n("a<u>b</u>a", "bab<u>a</u>")\nThe underlined portions are the substrings that are chosen from s and t.\n</pre>\n<strong>Example 2:</strong>\n\n<pre>\n<strong>Input:</strong> s = "ab", t = "bb"\n<strong>Output:</strong> 3\n<strong>Explanation:</strong> The following are the pairs of substrings from s and t that differ by 1 character:\n("<u>a</u>b", "<u>b</u>b")\n("<u>a</u>b", "b<u>b</u>")\n("<u>ab</u>", "<u>bb</u>")\nThe underlined portions are the substrings that are chosen from s and t.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= s.length, t.length <= 100</code></li>\n\t<li><code>s</code> and <code>t</code> consist of lowercase English letters only.</li>\n</ul>\n",
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"Take every substring of s, change a character, and see how many substrings of t match that substring.",
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"sampleTestCase": "\"aba\"\n\"baba\"",
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