Solution Review: Big (O) of Nested Loop with Addition

fn main(){
    let n = 10; 
    let mut sum = 0; 
    let pie = 3.14; 
    for i in (0..n).step_by(3){ // O(n/3)
        println!("{}",pie); // O(n/3)
        for j in (0..n).step_by(2){ // O(n/3)*O(n/2)
            sum=sum+i; // O(n/3)*O(n/2)
            println!("{}",sum); // O(n/3)*O(n/2)
        }
    }
}