LongestSubstringWithoutRepeatingCharacters.cpp

class Solution {
public:
    int lengthOfLongestSubstring(string s) {
        int maxLen = 0;
        int pos = 0;
        int lastpos = -1;
        unordered_map<char,int> m;
        m.clear();
        for(int i=0;i<s.length();i++) {
            if(m.find(s[i]) != m.end()) {
                pos = m.find(s[i])->second;
                for(int j=pos;j>lastpos;j--) {
                    if(m.find(s[j]) != m.end())
                        m.erase(m.find(s[j])); 
                }
                lastpos = pos;
                m.insert({s[i],i});
            } else {
                m.insert({s[i],i});
            }
            if(maxLen < m.size()) {
                maxLen = m.size();
            }
        }
        return maxLen;
    }  
};

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);
        
        int ret = Solution().lengthOfLongestSubstring(s);

        string out = to_string(ret);
        cout << out << endl;
    }
    return 0;
}