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Author: assassint2017

Longest Palindromic Substring/Longest_Palindromic_Substring.cpp

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+// Runtime: 48 ms, faster than 52.20% of C++ online submissions for Longest Palindromic Substring.
+// Memory Usage: 16 MB, less than 39.08% of C++ online submissions for Longest Palindromic Substring.
+
+class Solution {
+public:
+	string longestPalindrome(string s) {
+		// 边界条件处理
+		string res = "";
+		if (s.length() == 0) return res;
+
+		int maxLength = 0;
+		for (int center = 0; center < s.length(); ++center) {
+			int curLength[] = { 1, 0 }, leftPtr[] = { center, center + 1 }, rightPtr[] = { center, center };
+			for (int i = 0; i < 2; ++i) {
+				while (--leftPtr[i] >= 0 && ++rightPtr[i] < s.length() && s[leftPtr[i]] == s[rightPtr[i]])
+					curLength[i] += 2;
+
+				if (curLength[i] > maxLength) {
+					res = s.substr(++leftPtr[i], curLength[i]);
+					maxLength = curLength[i];
+				}
+			}
+		}
+		return res;
+	}
+};