Add subject and test for the exercise `hashing`

rust/tests/hashing_test/Cargo.lock

@@ -0,0 +1,12 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "hashing"
+version = "0.1.0"
+
+[[package]]
+name = "hashing_test"
+version = "0.1.0"
+dependencies = [
+ "hashing",
+]

rust/tests/hashing_test/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "hashing_test"
+version = "0.1.0"
+authors = ["Augusto <aug.ornelas@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+hashing = { path = "../../../../rust-piscine-solutions/hashing"}

rust/tests/hashing_test/src/main.rs

@@ -0,0 +1,41 @@
+// Given a list of integers (Vec<i32>) write three functions
+// Write a function called `mean` that calculates the `mean` (the average value) of all the values in the list
+// Write a function called `median` that calculates the `median` (for a sorted list is the value in the middle)
+// Write a function called `mode` that calculates the mode (the value
+// that appears more often)
+
+use hashing::*;
+
+#[allow(dead_code)]
+fn main() {
+	println!("Hello, world!");
+	let v = vec![4, 7, 5, 2, 5, 1, 3];
+	println!("mean {}", mean(&v));
+	println!("median {}", median(&v));
+	println!("mode {}", mode(&v));
+}
+
+use std::f64;
+
+#[allow(dead_code)]
+fn approx_eq(a: f64, b: f64) -> bool {
+	(a - b).abs() < f64::EPSILON
+}
+
+#[test]
+fn test_mean() {
+	let v = vec![4, 7, 5, 2, 5, 1, 3];
+	assert!(approx_eq(mean(&v), 3.857142857142857));
+}
+
+#[test]
+fn test_median() {
+	let v = vec![4, 7, 5, 2, 5, 1, 3];
+	assert_eq!(median(&v), 4);
+}
+
+#[test]
+fn test_mode() {
+	let v = vec![4, 7, 5, 2, 5, 1, 3];
+	assert_eq!(mode(&v), 5);
+}

subjects/hashing/README.md

@@ -0,0 +1,51 @@
+## hashing
+
+### Instructions
+
+Given a list of integers (Vec<i32>) write three functions
+
+Write a function called `mean` that calculates the `mean` (the average value) of all the values in the list
+
+Write a function called `median` that calculates the `median` (for a sorted list is the value in the middle)
+
+Write a function called `mode` that calculates the mode (the value
+that appears more often)
+
+### Expected Functions
+
+```rust
+fn mean(list: &Vec<i32>) -> f64 {
+}
+
+fn median(list: &Vec<i32>) -> i32 {
+}
+
+fn mode(list: &Vec<i32>) -> i32 {
+}
+```
+
+### Usage
+
+Here is a program to test your function.
+
+```rust
+use hashing;
+
+fn main() {
+	println!("Hello, world!");
+	let v = vec![4, 7, 5, 2, 5, 1, 3];
+	println!("mean {}", hashing::mean(&v));
+	println!("median {}", hashing::median(&v));
+	println!("mode {}", hashing::mode(&v));
+}
+```
+
+And its output
+
+```console
+student@ubuntu:~/[[ROOT]]/test$ cargo run
+mean 3.857142857142857
+median 4
+mode 5
+student@ubuntu:~/[[ROOT]]/test$
+```