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v03-l4-findOutput

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What is the output of this code ?

#include <iostream>
using std::cout, std::endl;

int main() {
    int i = 1;
    {
        int& i = i;
        i += 1;
    }
    cout << i << endl;
}

???

The code actually can be compiled, but compiler raises some error about uninitialized reference i for the following line :

int& i = i;

Then during execution, we may get a segmentation fault error : the program initializes the reference int& i with itself, and cannot actually bind it to the int i variable defined at the first line of the main function.

It's a limitation of C++ (but tbh, this case is kinda weird and not really a good coding example). To correct it, one can consider another naming for the reference, for instance :

int& _i = i;
_i += 1;

then it would modify the i value as expected and output 2 in the terminal when executing the code.