diff --git a/trivial/leetcode/source/q2982.cpp b/trivial/leetcode/source/q2982.cpp
new file mode 100644
index 0000000..a1c5006
--- /dev/null
+++ b/trivial/leetcode/source/q2982.cpp
@@ -0,0 +1,32 @@
+#include "common.h"
+
+class Solution {
+public:
+    int maximumLength(string s) {
+        // 只需记录超过 3 的最长的字符串
+        vector<vector<int>> len(26, vector<int>());
+        for (int i = 0; i < s.size(); i++) {
+            for (int j = i; i + j < s.size() && s[i] == s[i + j]; j++) {
+                len[s[i] - 'a'].emplace_back(j - i + 1);
+            }
+        }
+
+        int max_cnt = -1;
+
+        for (int i = 0; i < 26; i++) {
+            sort(len[i].begin(), len[i].end(), greater<int>());
+            for (int j = 0; j + 2 < len[i].size(); ++j) {
+                if (len[i][j] == len[i][j + 1] && len[i][j + 1] == len[i][j + 2]) {
+                    max_cnt = max(max_cnt, len[i][j]);
+                }
+            }
+        }
+        return max_cnt;
+    }
+};
+
+int main(int argc, char const* argv[]) {
+    Solution so;
+    print(so.maximumLength("aaaa"));
+    return 0;
+}