Solution as on 27-06-2022 07:00 am

Author: knockcat

0005. Longest Palindromic Substring.cpp

@@ -0,0 +1,39 @@
+// 5.✅ Longest Palindromic Substring
+
+class Solution
+{
+public:
+    string longestPalindrome(string s)
+    {
+        int n = s.size();
+        vector<vector<int>> t(n, vector<int>(n, 0));
+
+        string ans;
+        int maxlen = 0;
+
+        for (int diff = 0; diff < n; ++diff)
+        {
+            for (int i = 0, j = i + diff; j < n; ++i, ++j)
+            {
+                if (i == j)
+                    t[i][j] = 1;
+                else if (diff == 1)
+                    t[i][j] = (s[i] == s[j]) ? 2 : 0;
+                else
+                {
+                    if (s[i] == s[j] && t[i + 1][j - 1])
+                        t[i][j] = t[i + 1][j - 1] + 2;
+                }
+                if (t[i][j])
+                {
+                    if (j - i + 1 > maxlen)
+                    {
+                        maxlen = j - i + 1;
+                        ans = s.substr(i, maxlen);
+                    }
+                }
+            }
+        }
+        return ans;
+    }
+};