How to select a random number from two vectors with matching indices

I am trying to select a random number from two vectors, but they need to have matching indices. For example, if a random number in vs vector is 2, then the number selected from vd vector needs to be 7. Thanks!

extern crate rand;

use rand::Rng;

fn main() {
    let vs = vec![0, 1, 2, 3, 4];
    let vd = vec![5, 6, 7, 8, 9];
    let mut ww = Vec::with_capacity(2);
    let mut qq = Vec::with_capacity(2);
    let sample_num = 2;
    let mut num_sam = 0;
    while sample_num > num_sam {
        let mut ff = rand::thread_rng().choose(&vs);
        let mut cc = rand::thread_rng().choose(&vd);
        let mut index = vs.iter().position(|&r| r == ff).unwrap();
        let mut index1 = vd.iter().position(|&r| r == cc).unwrap();
        if index == index1 {
            ww.push(ff);
            qq.push(cc);

        }
        num_sam += 1;
    }

    println!("{:?}, {:?}", ww, qq)
}