Simple Program in Rust to Count Prime Numbers Linearly

PrimeCounter.rs

use std::io;

fn is_prime(n: i32) -> bool
{
    for i in 2..n
    {
        let p = n % i;
        if p == 0
        {
            return false;
        }
    }
    return true;
}

fn main()
{
    loop
    {
        println!("Find Prime Number From 1 to : ");

        let mut r = String::new();

        io::stdin().read_line(&mut r)
            .expect("Failed to read line");

        let r: i32 = match r.trim().parse()
        {
            Ok(num) => num,
            Err(_) => continue,
        };

        let mut y: i32 = 0;
        for x in 2..=r
        {
            if is_prime(x) == true
            {
                y = y + 1;
            }
        }

        println!("There are {} Prime Numbers", y);
        break;
    }
}