C question: Why the (condition) in for loop should be relevant to the (update statement)

Question

For example here

Int i = 0;
Int x = 0;
For (i = 1; i < 5; i++)

Why can't i just replace the ( i++) with (x++ )
Maybe i want to add that 1 to the (x) not to the (i) for some reason i want
So why can't i do that

Answer 1

You can, but look again at the condition, the loop was supposed to continue repetition while i < 5. If you increment value of <x> then the condition ( i < 5 ) will remain true (as <i> was zero and never got incremented) for eternity, and your loop goes round infinitely.

Answer 2

u can but it will be an infinite loop since every loop u dont add any i which i will always be 0.

if u want to add both variables on every loop u can do it this way

for (i = 0; i < 5; i++, x++)