2024-02-21 회문은 회문아니야!!

Munbin-Lee/README.md

@@ -35,4 +35,5 @@
 | 32차시 | 2024.01.30 |  백트래킹  | <a href="https://www.acmicpc.net/problem/17114">하이퍼 토마토</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/124 |
 | 33차시 | 2024.02.04 |  정수론  | <a href="https://www.acmicpc.net/problem/14905">소수 4개의 합</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/128 |
 | 34차시 | 2024.02.06 |  구현  | <a href="https://www.acmicpc.net/problem/1756">피자 굽기</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/133 |
+| 36차시 | 2024.02.21 |  문자열  | <a href="https://www.acmicpc.net/problem/15927">회문은 회문아니야!!</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/143 |
 ---

Munbin-Lee/문자열/36-회문은 회문아니야!!.cpp

@@ -0,0 +1,39 @@
+#include <iostream>
+#include <unordered_set>
+
+using namespace std;
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    string s;
+    cin >> s;
+
+    if (unordered_set<char>(s.begin(), s.end()).size() == 1) {
+        cout << "-1";
+        return 0;
+    }
+
+    auto isPalindrome = [](string &s) {
+        int lo = 0;
+        int hi = s.size() - 1; // NOLINT
+
+        while (lo < hi) {
+            if (s[lo] != s[hi]) return false;
+            lo++;
+            hi--;
+        }
+
+        return true;
+    };
+
+    if (!isPalindrome(s)) {
+        cout << s.size();
+        return 0;
+    }
+
+    cout << s.size() - 1;
+
+    return 0;
+}