#include <iostream>
int main() {
int a = 0;
std::cout << (a++) << "\n"; // Postfix ++, that you used. Prints 0
std::cout << a << "\n"; // but now a is 1.
std::cout << (++a) << "\n"; // Prefix ++, increases a and returns the increased value => Prints 2
std::cout << a << "\n"; // Prints 2
}
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