best way to add more value to something

how can i make a levelup system that easy to code

like i wont have to

PHP:

if(players level equals 1){
set level up cost(22)
}
if(players level equals 2){
set level up cost (44)
}

i could just make it add 22 per levelup

 

Both — a linear and exponential levelling system are easy to code.
You specified you wanted to add 22 xp per level, which is a linear levelling system.

Growth chart of linear vs exponential:

Red = Linear
Blue = Exponential
Green = Exponential

Code:

levelup_cost = 22 * x
//x = xp level

While that code is only applicable for levels 1 to infinity, if you are starting from level 0, you could simply add a +1 to the level.

Code:

levelup_cost = 22 * (x + 1)

If you want to go with an exponential growth, you could try:

Code:

levelup_cost = x ** 2
//Or 2 ** x (NOTE: they're not the same, see the graph)
//2 is the growth factor
//The bigger the growth factor, the larger is the levelup_cost

Both seem simple, preferences?