fn main() {
    proconio::input! {
        mut l: u64,
    }
    while l > 1 {
        if l == 3 {
            print!("7");
            break;
        } else {
            print!("1");
        }
        l /= 2;
    }
    println!();
}

fn proc(a: u64, b: u64) -> u64 {
    b.div_ceil(a)
}

#[cfg(test)]
mod test {
    use super::*;
    #[test]
    fn test() {
        assert_eq!(proc(2, 5), 3);
    }
}