Using The Remainder

The % remainder operator is surprigingly useful in combination with the comparison operators. One example is using it to divide content into groups.

For exmaple, if we use % with an incrementing number on the left side and 3 on the right side it will return zero for everything that's divisible by three with no remainder. If we run a comparison against that value in an if statement we can process every third value differently.

Take this code for example that outputs:

1 <----
2 <----
----> 3
4 <----
5 <----
----> 6
7 <----
8 <----
----> 9
10 <----

SOURCE CODE

fn main() {
  let start = 1;
  let end = 10;
  let target = 3;

  for alfa in start..=end {
    if alfa % target == 0 {
      println!("----> {alfa}")
    } else {
      println!("{alfa} <----")
    }
  }
}

CODE RUNNER