I don't understand what do x++ and x-- do

Question

Im at a part where I need to figure out the output of code but I don't understand what the -- and ++ does even after repeating the lessons with this part

Answer 1

x++;
is the same as
x=x+1;
or
x+=1;
It increases the number by 1.

-- decreases the number by 1

Answer 2

++ and -- are operators. something that is used for simplification.
saying x++ is the same as adding one to x or x += 1
and the orientation of the operator matters as well. if you were to print out the variable x, then x++ :
cout << x << " " << x++ << endl;
you would see
5 5
however if you were to print out
cout << x << " " << ++x << endl;
you would see
5 6
because the operator incremented the variable before the output where as the one above did it after the output. the number will increment as long as the ++ operator is used somewhere around it.

this is the opposite for --
using this operator will decrement the variable by one. in similar fashion with the out put as well, you could have --y or y--. they both subtract one just at different times.

normally we would use x++ (like in for loops) this way it can test the variable x then increment it when its done.

hope this helps!!

Answer 3

int a=3;
int b=2;
b=a++;// this time b value is 3
cout<<++b;//this time b value will increase by 1 than it will print. print value will be
//4
cout<<a;//this time a value is 4

Answer 4

x++
same as x=x+1 or x+=1
increase x value by 1
and
x--
same as x=x-1 or x-=1
Decrease x value by 1

Answer 5

ok but then tell me why the output of this code is: 4

int a = 3;
int b=2;
b=a++; //So here we forget that b=2 because the value is changed to b=4
cout<<++b; //But what happens here why is the output still 4 not 5 I dont understand the operators BEFORE the variable

Answer 6

b=a++; // b gets assigned the value of a. a is increased by 1 after the assignment

cout<<++b; // b is increased by 1 before it is printed

Answer 7

Why is b=2 since a=3 and then b changes its value from 2 to b=a(a is 3) ++ (b increases by 1 because of the ++) 3+1=4 so im still confused

Answer 8

int a=3;
int b=2;

b=a++;
// b=a (b=3) and a=a+1
// b==3, a==4

cout<<++b;
// b is increased by 1 (3+1=4) and then printed