diff --git a/Cargo.lock b/Cargo.lock
index ac9d3e1..5c7718f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -71,12 +71,24 @@ version = "0.3.55"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f5f3913fa0bfe7ee1fd8248b6b9f42a5af4b9d65ec2dd2c3c26132b950ecfc2"
 
+[[package]]
+name = "getrandom"
+version = "0.2.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "be4136b2a15dd319360be1c07d9933517ccf0be8f16bf62a3bee4f0d618df427"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "wasi",
+]
+
 [[package]]
 name = "hash_test"
 version = "0.1.0"
 dependencies = [
  "fasthash",
  "hashbrown",
+ "rand 0.8.5",
 ]
 
 [[package]]
@@ -110,6 +122,12 @@ version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd8b5dd2ae5ed71462c540258bedcb51965123ad7e7ccf4b9a8cafaa4a63576d"
 
+[[package]]
+name = "ppv-lite86"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
+
 [[package]]
 name = "rand"
 version = "0.4.6"
@@ -123,6 +141,27 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core 0.6.4",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.6.4",
+]
+
 [[package]]
 name = "rand_core"
 version = "0.3.1"
@@ -138,6 +177,15 @@ version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc"
 
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
+]
+
 [[package]]
 name = "rdrand"
 version = "0.4.0"
@@ -159,6 +207,12 @@ version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
+[[package]]
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -187,5 +241,5 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e0eeda34baec49c4f1eb2c04d59b761582fd6330010f9330ca696ca1a355dfcd"
 dependencies = [
- "rand",
+ "rand 0.4.6",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index a24bed3..f044f34 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,7 @@ edition = "2018"
 [dependencies]
 hashbrown = "0.14"
 fasthash = "0.4.0"
+rand = "0.8.5"
 
 [profile.release]
 opt-level = 3
diff --git a/src/main.rs b/src/main.rs
index a16beef..e4031f1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,19 +1,23 @@
 use fasthash::spooky;
 use hashbrown::HashSet;
-use std::fs::File;
-use std::io::{BufReader, BufRead};
+use rand::prelude::*;
 use std::time::Instant;
 
+const CAP: i32 = 1000000;
+
 fn main() {
-    let arg: Vec<String> = std::env::args().collect();
-    if arg.len() != 2 {
-        eprintln!("{} numbers.txt", std::env::args().nth(0).unwrap());
-        std::process::exit(1);
+    let mut v: Vec<i32> = Vec::with_capacity(CAP as usize);
+    let mut rng = thread_rng();
+
+    let mut i = 0i32;
+    loop {
+        if i == CAP {
+            break;
+        }
+        i += 1;
+
+        v.push(rng.gen_range(-CAP..CAP));
     }
-    let name = &arg[1];
-    let f = File::open(name).expect("file can't open");
-    let reader = BufReader::new(f);
-    let v: Vec<i32> = reader.lines().map(|x| x.unwrap().parse::<i32>().unwrap()).collect();
 
     {
         let mut h = HashSet::with_hasher(spooky::Hash64);
@@ -28,7 +32,6 @@ fn main() {
         bench_std(&v, &mut h, true);
         bench_std(&v, &mut h, false);
     }
-
 }
 
 fn bench_swiss(v: &Vec<i32>, h: &mut HashSet<i32, spooky::Hash64>, ins: bool) {
@@ -36,16 +39,20 @@ fn bench_swiss(v: &Vec<i32>, h: &mut HashSet<i32, spooky::Hash64>, ins: bool) {
 
     if ins {
         for i in v {
-        h.insert(*i);
+            h.insert(*i);
         }
     } else {
         for i in v {
             h.contains(i);
         }
     }
-    
+
     let elapsed = now.elapsed().as_millis();
-    println!("swiss {} => {}ms", if ins { "insert" } else { "search" }, elapsed);
+    println!(
+        "swiss {} => {}ms",
+        if ins { "insert" } else { "search" },
+        elapsed
+    );
 }
 
 fn bench_std(v: &Vec<i32>, h: &mut std::collections::HashSet<i32, spooky::Hash64>, ins: bool) {
@@ -53,14 +60,18 @@ fn bench_std(v: &Vec<i32>, h: &mut std::collections::HashSet<i32, spooky::Hash64
 
     if ins {
         for i in v {
-        h.insert(*i);
+            h.insert(*i);
         }
     } else {
         for i in v {
             h.contains(i);
         }
     }
-    
+
     let elapsed = now.elapsed().as_millis();
-    println!("std  {} => {}ms", if ins { "insert" } else { "search" }, elapsed);
+    println!(
+        "std  {} => {}ms",
+        if ins { "insert" } else { "search" },
+        elapsed
+    );
 }