simplify the README

README.md

@@ -7,27 +7,9 @@ cargo add plnk --git https://gitlab.isae-supaero.fr/a.stevan/plnk --tag 0.2.0  #
 ```
 
 ## usage
-```rust
-use rand::Rng;
-
-fn arithmetic(b: &plnk::Bencher) {
-    plnk::bench(b, "addition", || plnk::timeit(|| 1 + 2));
-    plnk::bench(b, "substraction", || plnk::timeit(|| 1 - 2));
-    plnk::bench(b, "multiplication", || plnk::timeit(|| 2 * 3));
-}
-
-fn random(b: &plnk::Bencher) {
-    let mut rng = rand::thread_rng();
-    plnk::bench(b, "sampling", || plnk::timeit(|| rng.gen::<u128>()));
-}
-
-fn main() {
-    const NB_MEASUREMENTS: usize = 10;
-    let bencher = plnk::Bencher::new(NB_MEASUREMENTS);
-
-    arithmetic(&bencher.with_name("arithmetic"));
-    random(&bencher.with_name("random"));
-}
+see the [arithmetic example](`examples/arithmetic.rs`) which can be used as
+```shell
+cargo run --release --example arithmetic -- --nb-measurements 1000
 ```
 
 ## the output of PLNK