Why the output is 20 ?

Question

#include <iostream>
using namespace std;

int main()
{int a=1;
int b =9;
a= ++b;
cout<<a+b;
}

Answer 1

Answer is: a=++b means a=10 because int b=9 so pre increment of b is 10. Then a=10,b=10 .so final answer of a+b= 20

Answer 2

a=++b ;
means
a=b+1 ;
given b=9
a=10

a+b
a=10 and b=10(as ++b incremented b also)

so OUTPUT: 20

Answer 3

Pre increment operator increments value of <b> before returning the result. So that when you assigned ++b to variable <a> the value of <b> had been incremented to become 10.

Then value of <b> is assigned to variable <a>, which makes both value of <a> and <b> equal 10. Next you output <a> (10) + <b> (10). And that's how it outputs 20.

Answer 4

Thank you .

Answer 5

Ipang does it the giving value of 10 to b too?

Answer 6

~ swim ~ What if I wrote b++?