Finds the ceiling value of square root with Rust.

ceil_sqrt.rs

/// Finds the ceiling value of square root of `n`.
pub fn ceil_sqrt(n: i64) -> i64 {
    let mut base = (n as f64).sqrt() as i64 - 1;
    while (base + 1) * (base + 1) <= n {
        base += 1;
    }
    base
}