Unexpected output of a Call-by-Reference

[athrun200]

In the code below, the function will be first executed, producing the following data
x = 15
y = 11
x+y = 26

as there is a "&" operator in front of x, so the value of x will be changed to 15.

I expect the result as
26
15
10

But the program give me
26
5
10

What's wrong?

#include <iostream>
using namespace std;

int function(int& x, int y)
{
	x = x+y;
	y++;
	return x+y;
}

int main()
{
	int x = 5, y(10);
	cout << function(x,y) << endl << x << endl << y << endl;

	return 0;
}

[cire]

The order of evaluation for arguments to the chained operator<< are not specified.

Try:

    cout << function(x,y) << endl ;
    cout << x << endl << y << endl ;

[coder777]

the problem is the order of evaluation. You expect that function() is executed first, but in fact it starts with the last expression

[athrun200]

but in fact it starts with the last expression

Do you mean that the computer read from right to left?

[cire]

Do you mean that the computer read from right to left?

It may begin with the last. It may begin with the first. It may begin with the middle. The order is unspecified, so the compiler is perfectly correct in whatever order it takes.