#include<iostream>
#include<set>
 
int main() {
    // Create a set object holding integers
    std::set<int> mySet {1,2,3,4,-5};
    if (mySet.count(1) != 0) {
        std::cout << "1 : is not an element of myset" << std::endl;   
    }
    else {
        std::cout << "1 : is a element of mySet" << std::endl;
    }
    if (mySet.count(12) == 0) {
        std::cout << "12 : is not an element of myset" << std::endl;   
    }
    else {
        std::cout << "12 : is a element of mySet" << std::endl;
    }
 
    return 0;
}

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