c++ - Why does a const reference behave differently when assigned an l-value and r-value? -

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given code sample below;

#include<iostream>  using namespace std;  int main(){     int = 4;     const int &b = a;     const int &c = * 2;     = 10;     cout << b << endl;     cout << c << endl;     return 0; }

when run this, output 

10 8

why c++ designed behave differently when assigning l-value , r-value const references?

the expression:

const int &c = * 2;

does not bind resulting reference c a. instead binds rvalue result of expression a * 2, temporary object no longer has a - changing a not affect it.

this opposed b, reference object a.


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