Merge pull request #1586 from AlgorithmWithGod/khj20006

[20251205] BOJ / P5 / 가장 긴 팰린드롬 부분 문자열 / 권혁준

Author: ShinHeeEul

khj20006/202512/05 BOJ P5 가장 긴 팰린드롬 부분 문자열.md

@@ -0,0 +1,24 @@
+```cpp
+#include <bits/stdc++.h>
+using namespace std;
+
+string t, s = "#";
+int A[222222]{}, C = 1, R = 1;
+
+int main() {
+	cin.tie(0)->sync_with_stdio(0);
+
+	cin >> t;
+	for (char i : t) s += i, s += "#";
+	
+	int ans = 0;
+	for (int i = 1; i < s.size(); i++) {
+		A[i] = min(A[2 * C - i], R - i);
+		while (i > A[i] && i + A[i] + 1 < s.size() && s[i - A[i] - 1] == s[i + A[i] + 1]) A[i]++;
+		if (i + A[i] >= R) C = i, R = i + A[i];
+		ans = max(ans, A[i]);
+	}
+	cout << ans;
+
+}
+```