Rust

extern crate rand;
extern crate rayon;
use rand::Rng;
use rand::distributions::Alphanumeric;
use rayon::prelude::*;

use std::time::Instant;

fn main() {
    for _ in 0..10 {
        let timer = Instant::now();
        let vec: Vec<String> = (0..100_000)
            .into_par_iter()
            .map_init(
                || rand::thread_rng(),
                |rng, _| rng.sample_iter(&Alphanumeric).take(100).collect()
            ).collect();

        let overall_count: u32 =
            (0..1000)
                .into_par_iter()
                .fold(|| 0u32, |acc, _| {
                    let needle: String = rand::thread_rng()
                        .sample_iter(&Alphanumeric)
                        .take(20)
                        .collect();
                    if (&vec).iter().any(|s100| {
                        s100.contains(&needle)
                    }) {
                        acc + 1
                    } else {
                        acc
                    }
                })
                .sum();

        println!("Found {} instances of in {:.2} secs", overall_count,
                 timer.elapsed().as_secs_f64());
    }
}