I was trying a problem in which I wanted to delete some elements from the set while iterating over the elements of the set.

Link to the problem: Problem C, Educational Round #108

Pseudo Code

for(condition in list_of_conditions):
   for(element X in set):
      if(condition(X) is false):
         remove X from the set
      else:
         answer += result(X)

However, I failed to implement this in an optimized way. I wonder what are some of the shortest and most optimized codes to implement this idea...

Please share your ideas. Thank you!

Failed implementation (Runtime error)

for (condition in list_of_conditions)
{
   for(int X: set)
   {
      if(condition(X) == false)
         set.erase(X);
      else
         answer += X;
   }
}

Accepted implementation

for (condition in list_of_conditions)
{
   Create an empty set (set2)
   for(int X: set)
   {
      if(condition(X) == true)
      {
         answer += X;
         set2.insert(X);
      }
   }
   set.clear();
   for(element X in set2)
      set.insert(X);
}

Link to the Question: 576A

Link to my code: Code

I was trying this question on Number theory and faced this error "Wrong Answer cannot distinguish 1 and 727". I couldn't detect the reason for the incorrect output. My code runs fine and gives correct result for the same input (test case 16) on other platform's IDEs. Please help!!

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