leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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1081.cpp (546B)

      1 class Solution {
      2   public:
      3     string smallestSubsequence(const string &s) {
      4         uint16_t last[128] = {0}, seen[128] = {0};
      5         string res = "";
      6 
      7         for (int i = 0; i < s.size(); i++)
      8             last[s[i]] = i;
      9         for (int i = 0; i < s.size(); i++) {
     10             if (seen[s[i]]++) continue;
     11             while (!res.empty() && res.back() > s[i] && i < last[res.back()]) {
     12                 seen[res.back()] = 0;
     13                 res.pop_back();
     14             }
     15             res.push_back(s[i]);
     16         }
     17         return res;
     18     }
     19 };