diff --git a/src/algorithms/randomness/rand-choose.md b/src/algorithms/randomness/rand-choose.md
index acf0bed..8a95c63 100644
--- a/src/algorithms/randomness/rand-choose.md
+++ b/src/algorithms/randomness/rand-choose.md
@@ -2,25 +2,30 @@
 
 [![rand-badge]][rand] [![cat-os-badge]][cat-os]
 
-Randomly generates a string of given length ASCII characters with custom user-defined bytestring, with [`choose`].
+Randomly generates a string of given length ASCII characters with custom
+user-defined bytestring, with [`gen_range`].
 
 ```rust
 extern crate rand;
 
-use rand::seq::SliceRandom;
-
 fn main() {
-    const CHARSET: &[u8] =  b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
-    abcdefghijklmnopqrstuvwxyz\
-    0123456789)(*&^%$#@!~";
-
+    use rand::Rng;
+    const CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
+                            abcdefghijklmnopqrstuvwxyz\
+                            0123456789)(*&^%$#@!~";
+    const PASSWORD_LEN: usize = 30;
     let mut rng = rand::thread_rng();
-    let password: Option<String> = (0..30)
-        .map(|_| Some(*CHARSET.choose(&mut rng)? as char))
+
+    let password: String = (0..PASSWORD_LEN)
+        .map(|_| {
+            let idx = rng.gen_range(0, CHARSET.len());
+            // This is safe because `idx` is in range of `CHARSET`
+            char::from(unsafe { *CHARSET.get_unchecked(idx) })
+        })
         .collect();
 
     println!("{:?}", password);
 }
 ```
 
-[`choose`]: https://docs.rs/rand/*/rand/trait.Rng.html#method.choose
+[`gen_range`]: https://docs.rs/rand/*/rand/trait.Rng.html#method.gen_range