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  1. #include <iostream>
  2. #include <vector>
  3. #include <unordered_set>
  4.  
  5. using namespace std;
  6.  
  7. struct hasher // Just an example of hash function
  8. {
  9.   size_t operator()(const std::vector<int>& val) const
  10.   {
  11.     size_t ans = 0;
  12.     std::hash<int> hasher;
  13.     for (auto v : val)
  14.     {
  15.       ans = ans * 2654435761 + hasher(v);
  16.     }
  17.     return ans;
  18.   }
  19. };
  20.  
  21. int main()
  22. {
  23.   unordered_set<vector<int>, hasher> si;
  24.   si.insert({ 1, 2 });
  25.   si.insert({ 3, 4 });
  26.   si.erase({ 1, 2 });
  27.   if (si.find({ 1, 2 }) != si.end())
  28.   {
  29.     cout << "{1, 2} have found" << endl;
  30.   }
  31.   if (si.find({ 3, 4 }) != si.end())
  32.   {
  33.     cout << "{3, 4} have found" << endl;
  34.   }
  35.   return 0;
  36. }
Success #stdin #stdout 0s 3416KB
comments (?)
stdin 
Standard input is empty
stdout 
{3, 4} have found
https://ideone.com/uoiKLy
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
public

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