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Question #208 Difficulty: 1

According to the C++17 standard, what is the output of this program?

    #include <iostream>
#include <map>
using namespace std;

bool default_constructed = false;
bool constructed = false;
bool assigned = false;

class C {
    C() { default_constructed = true; }
    C(int) { constructed = true; }
    C& operator=(const C&) { assigned = true; return *this;}

int main() {
    map<int, C> m;
    m[7] = C(1);

    cout << default_constructed << constructed << assigned;


What does the [] operator do if the key is not present?


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