increment/decrement operators

Ok, So I got into math functions in C++ and it showed this which is totally confusing me. I'm just not comprehending what it does.

Code:

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++count;       

//OR

total = 6 + count--;

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I'm just not getting what that is meaning. Any help?

Code:

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++count;

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Increases count by 1.

Code:

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count--;

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Decreases count by 1.

There are post and pre incremenet/decrement operators....
which increment or decrement the variables before or after their usage.....

Here is an example:

Code:

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#include <stdio.h>

int main()
{
 int i=1;

 printf("i=%d\n",i);        /*i=1*/
 i++;
 printf("i=%d\n",i);        /*i=2*/
 printf("i=%d\n",i++);      /*i=2*/
 printf("i=%d\n",i);        /*i=3*/
 printf("i=%d\n",++i);      /*i=4*/

 return 0;
}

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I'm still not understanding and CodingMaster I'm using C++ not C.

It really doesn't get much simpler.

int c = 5;

sets "c" to 5.

c++

makes "c" equal 6.

c--

makes "c" equal 5 again.

Here's codingmasters code in C++...

Code:

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// include stream header files here...

int main()
{
 int i=1;

 cout << i;        /*i=1*/
 i++;
 cout << i;        /*i=2*/
 cout << i++;      /*i=2*/
 cout << i;        /*i=3*/
 cout << ++i;      /*i=4*/

 return 0;
}

---

Code:

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#include <iostream>
using namespace std;

int main()
{
 int i=1;

 cout << i;        /*i=1*/
 i++;
 cout << i;        /*i=2*/
 cout << i++;      /*i=2*/
 cout << i;        /*i=3*/
 cout << ++i;      /*i=4*/

 return 0;
}

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:P

To expound on Elixa's message... if the ++ is before the variable, it is incremented by one BEFORE it is used. If it is after, it gets incremented AFTER it is used. Same with --.

ok so 2 negatives minuses it by 1. opposite with positive. and its before or after depending on position.

mhmm.

heh, _Elixia_ did the work for me..... ;)

int x=5; // set x the value of x to 5

u use ++ for incrementation and -- for decrementation

++ is equal to +1
-- is equl to -1

so, u could write instead of ++ or -- for post incrementation / decrementation
x-=1; // equal to x=x-1
x+=1;// equal to x=x+1

when u use pre incrementation / decrementation.....

the compiler increments / decrements the variable first and then output its......
e.g.:

x--; // is equal to --x;

but.... have a look at this code:

Code:

---

#include <iostream>
using namespace std;
int main()
{
int x=5;
cout << x++ << endl; // cout: the value of x is 5 and after it increments it.....
cout << x << endl; // cout: the value of x is 6
cout << ++x <<endl; // cout: !!!now!!! we use pre incrementation: cout: the value of x is 7
return 0;
}

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Decremenation works like incrementation.....

Dec: -- (=-1)
Inc: ++ (=+1)

Don't forget the difference between postfix and prefix:

Code:

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int x=1;
int c=++x; //c will be 2 since it increments and then returns the value
x=1;
int y=x++; //y will be 1 since it returns the value then increments

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Ok cool thanks that helped me a bunch.