Omit first parameter in for loop

Question

In PHP, Java, C++ (and many other languages), for loops are used like this:

for(int i=0;i<10;i++)

If I already initialized i, how can I omit the initialization statement?

Answer 1

In Java, C++ and PHP it is completely valid to omit the initialization portion of the for loop

int i = 0;
...
for(; i < 10; i++);

This is true of most languages which have a for loop structure

Answer 2

for(; i < 10; i++) {
    ...
}

You can leave out any of the items in the for loop if they are not needed. You could also put in multiple things to do, or multiple conditions to check such as:

int j = 40;
for(int i = 0; i < 10 || j > 30; i++, j--) {}