add functions, prim, unit and tuple challenges solutions

Author: AlphonseMehounme

Rust/rustifinity/challenges/converting-numerical-types.rs

@@ -0,0 +1,3 @@
+pub fn numerical_type_conversion(n: i32) -> u32 {
+    n as u32
+}

Rust/rustifinity/challenges/functions.rs

@@ -0,0 +1,22 @@
+pub fn add(a: i32, b: i32) -> i32 {
+    // Step 1: implement addition
+    a + b
+}
+
+// Step 2:
+// Define a public function named `subtract`
+// that accepts two arguments of type `i32`
+// and returns an `i32`.
+// make sure you make the function public by using the `pub` keyword.
+pub fn subtract(a: i32, b: i32) -> i32 {
+    a - b
+}
+
+// Step 3:
+// Define a public function named `multiply`
+// that accepts two arguments of type `i32`
+// and returns an `i32`.
+// make sure you make the function public by using the `pub` keyword.
+pub fn multiply(a: i32, b: i32) -> i32 {
+    a * b
+}

Rust/rustifinity/challenges/mathematical-operations.rs

@@ -0,0 +1,4 @@
+pub fn math_operations(a: i32, b: i32) -> (i32, i32, i32, i32) {
+    // TODO: Return a tuple of 4 values: (sum, difference, multiply, divide)
+    (a + b, a - b, a * b, a / b)
+}

Rust/rustifinity/challenges/sum-of-array.rs

@@ -0,0 +1,8 @@
+pub fn sum_array(arr: &[i32]) -> i32 {
+    // TODO: Implement the function here
+    let mut sum: i32 = 0;
+    for el in arr {
+        sum += el;
+    }
+    sum
+}

Rust/rustifinity/challenges/the-unit-type.rs

@@ -0,0 +1,5 @@
+pub fn print_message() -> () {
+    // TODO: Implement the function here
+    println!("Hello, Rust!");
+    ()
+}

Rust/rustifinity/challenges/tuples.rs

@@ -0,0 +1,4 @@
+pub fn create_tuple(a: i32, b: f64, c: &str) -> (i32, f64, String) {
+    // TODO: Implement the function here
+    (a, b , String::from(c))
+}