solution(cpp): 5. Longest Palindromic Substring

5. Longest Palindromic Substring - C++
godkingjay · Oct 29, 2023 · d4cfdf4 · d4cfdf4
2 parents 124665d + 6a8b13b
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diff --git a/Medium/5. Longest Palindromic String/longestPalindromic.cpp b/Medium/5. Longest Palindromic String/longestPalindromic.cpp
@@ -0,0 +1,38 @@
+class Solution {
+public:
+    string longestPalindrome(string s) {
+        int n = s.length();
+        int st = 0;
+        int max_len = 1;
+
+        if(n == 1) return s;
+
+        for(int i=0; i < n-1; i++) {
+            int l = i, r = i;
+            while(l >= 0 && r < n && s[l] == s[r]) {
+                l--;
+                r++;
+            } 
+            int len = r-l-1;
+            if(len > max_len) {
+                max_len = len;
+                st = l+1;
+            }
+        }
+
+        for(int i=0; i < n-1; i++) {
+            int l = i, r = i+1;
+            while(l >= 0 && r < n && s[l] == s[r]) {
+                l--;
+                r++;
+            }
+            int len = r-l-1;
+            if(len > max_len) {
+                max_len = len;
+                st = l+1;
+            }
+        }
+
+        return s.substr(st, max_len);
+    }
+};
diff --git a/Medium/Longest Palindromic String/longestPalindromic.exe b/Medium/Longest Palindromic String/longestPalindromic.exe