Increment operator ++

apox01 (10)
Hi I am currently learning about operators and I am confused on the actual use of the incremental operator ++

What I know thus far is
-when its a prefix incremental operator the value returned is the value in the counter after it has been incremented.
-when its a postfix incremental operator the value returned is the value in the counter before it has been incremented.

So with code I have the following to try to see it in action

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//Header files
#include "stdafx.h"
#include <iostream>

using namespace std;

int main()
{
	//variables declared
        int a = 1;
	int b;
	int c;

	b = ++a; //passing value of 2 to b
        c = a++; //passing value of 1 to c

	cout << b << endl; //output is 2
	cout << c << endl; //output is 2
	
	cin.get();
	return 0;
}


So my question is the following, I understand why the printout is 2 for my b variable but for my c variable its also a 2? I thought it passed the value in variable a first giving me an output of 1?

I am very new only programming couple days, any help in understanding this would be appreciated.
Last edited on
Disch (13742)
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a = 1;

// here, a is 1

b = ++a; // a is incremented (a=2) then assigned to b (b=2)

// here, a is 2

c = a++; // a is assigned to c (c=2) then a is incremented (a=3)

// here, a is 3

/*
End result:

a = 3
b = 2
c = 2
*/

Last edited on
clanmjc (666)
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a = 1;
b = ++a; //a is incremented to 2 then returned
c = a++; //a is still 2 (from the last statement), a makes a copy of itself (2) 
             //and then increments itself to 3, but the copy is returned from the operator (2)
apox01 (10)
Darn I failed to notice that it was still a value of 2 from the last statement. I understand it a lot better now so thank you both.
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