Why the output of this code is 9 not 10? Plz explain 🙏

Question

#include <iostream>
using namespace std;

int main() {
int a=9;
{
int a=9;
a++;
}
cout<<a++;
return 0;
}

Answer 1

scope. The second a belongs to a inner block code and a++ increments the a in its scope

Answer 2

Arturop Got it
Thanks for explaining 🙏

Answer 3

Because you use post-increment operator when you send output of <a>. Had you used pre-increment operator, you'll get 10

cout << ++a; // output 10