### A newbie question regarding variable

when a=5, and how can a also = a+1 ? and which a does the result look for to + b ?

 ``1234567891011121314151617181920212223`` `````` // operating with variables #include using namespace std; int main () { // declaring variables: int a, b; int result; // process: a = 5; b = 2; a = a + 1; result = a - b; // print out the result: cout << result; // terminate the program: return 0; }``````
`=` is the assignment operator not comparison which is `==`.

In your case it takes `a` adds 1 to it and assigns it back to `a`. Shorter it would be `a++;` or `++a;` or `a += 1`. They all express the same.

 and which a does the result look for to + b ?
hm, I don't understand? Do you mean if it cares whether `result` is positive or not? No it doesn't. For this you may use abs():

http://www.cplusplus.com/reference/cstdlib/abs/?kw=abs
`a = 5; ` means, take the value on the right hand side of the = sign and store it in the variable to the left of the =.

`a = a + 1;` means first calculate the result of whatever is on the right, `a + 1` then after doing that, store the result in the variable on the left.

It can be useful to write down the name of each variable as a column heading. Then as each program line is executed, write down the value of each variable.

 ``` | a | b | result | ---------------------------------------------------- int a, b; | unknown | unknown | - | int result; | unknown | unknown | unknown | | | | | a = 5; | 5 | unknown | unknown | b = 2; | 5 | 2 | unknown | a = a + 1; | 6 | 2 | unknown | result = a - b; | 6 | 2 | 4 | ```
if i add `a = a + a`, would a be equal to 12 ? and does it have different outcomes if i change the order ?

like if i put
 ``123`` ``````a = 5 a = a + a a = a + 1``````

would a still be 6 ? or it would be 11 ? since a=5+5, and a=10+1...
"a" would be 11
you cant print out "a" in between
so whatever put to the last of the order will be calculated last right ? like staring from from line one to line three, from higher priority to lower, is that what you mean ?
 ``123`` ``````a = 5 a = a + a a = a + 1``````
Yes. Under ordinary circumstances the lines of code are executed in sequence, starting from the top and proceeding line by line.

That is, until you start adding loops, or if-else conditions, but none of those apply here.
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