Create LongestPalindromicSubstring

https://leetcode.com/problems/longest-palindromic-substring/

Author: itsgauravsingh

LongestPalindromicSubstring

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+#include <string>
+
+class Solution {
+public:
+    /*
+    bool isPalindrome(const string &s) {
+        string temp = s;
+        reverse(temp.begin(),temp.end());
+        return temp.compare(s) ? false : true ;
+    }
+    */
+    string longestPalindrome(string s) {
+        int length = s.length();
+        unordered_map<string,int> m;
+        for(int l=length;l>=0;l--) {
+            for(int i=0;i+l <= length; i++) {
+                string temp(s,i,l);
+                reverse(temp.begin(),temp.end());
+                if (s.compare(i,l,temp) == 0){
+                    reverse(temp.begin(),temp.end());
+                    return temp;
+                }
+            }
+        } 
+        
+        return "";
+    }
+};
+
+string stringToString(string input) {
+    assert(input.length() >= 2);
+    string result;
+    for (int i = 1; i < input.length() -1; i++) {
+        char currentChar = input[i];
+        if (input[i] == '\\') {
+            char nextChar = input[i+1];
+            switch (nextChar) {
+                case '\"': result.push_back('\"'); break;
+                case '/' : result.push_back('/'); break;
+                case '\\': result.push_back('\\'); break;
+                case 'b' : result.push_back('\b'); break;
+                case 'f' : result.push_back('\f'); break;
+                case 'r' : result.push_back('\r'); break;
+                case 'n' : result.push_back('\n'); break;
+                case 't' : result.push_back('\t'); break;
+                default: break;
+            }
+            i++;
+        } else {
+          result.push_back(currentChar);
+        }
+    }
+    return result;
+}
+
+int main() {
+    string line;
+    while (getline(cin, line)) {
+        string s = stringToString(line);
+        
+        string ret = Solution().longestPalindrome(s);
+
+        string out = (ret);
+        cout << out << endl;
+    }
+    return 0;
+}