Initial commit

Medium/longest-palindromic-substring/solution.cpp

@@ -0,0 +1,33 @@
+#include <string>
+
+class Solution {
+  public:
+    std::string longestPalindrome(std::string line) {
+        if (line.size() < 2) {
+            return line;
+        } else {
+            int size = 0, start = 0, left = 0, right = 0, middle = 0;
+            while (middle < line.size()) {
+                left = middle, right = middle;
+                while (right < line.size() - 1 &&
+                       line[right] == line[right + 1]) {
+                    ++right;
+                }
+
+                middle = right + 1;
+                while (right < line.size() - 1 && left > 0 &&
+                       line[right + 1] == line[left - 1]) {
+                    --left;
+                    ++right;
+                }
+
+                if (right - left + 1 > size) {
+                    start = left;
+                    size = right - left + 1;
+                }
+            }
+
+            return line.substr(start, size);
+        }
+    }
+};