add rand

random/src/main.rs

@@ -0,0 +1,21 @@
+use rand::distributions::{
+    Distribution, Uniform,
+};
+use rand_core::RngCore;
+
+fn main() {
+    let mut rng = rand::thread_rng();
+
+    println!("10 rands u32");
+    for _ in 0..10 {
+        let u = rng.next_u32();
+        println!("{}", u);
+    }
+
+    println!("10 rands -1.0 ~ 1.0");
+    let range = Uniform::new(-1.0f64, 1.0);
+    for _ in 0..10 {
+        let a = range.sample(&mut rng);
+        println!("{}", a);
+    }
+}