initial lab 01

lectures/01/src/arrays.rs

@@ -0,0 +1,52 @@
+pub fn run() {
+    println!("ARRAYS");
+
+    // in rust arrays are values
+    // unlike in c where arrays are an address
+    let a = [3, 2, 7, 6, 8];
+    println!("{a:?}"); // debug print
+
+    let mut a = [3, 2, 7, 6, 8];
+    a[0] = -3;
+    println!("{a:?}");
+
+    print_array5(a);
+    double_array5(&mut a);
+    print_array5_v2(&a);
+
+    super::slices::double(&mut a);
+}
+
+fn print_array5(a: [i32; 5]) {
+    // 0..5 is non inclusive
+    for i in 0..5 {
+        println!("{}", a[i]);
+    }
+
+    /* this works also
+       x is i32
+    for x in a {
+        println!("{x}")
+    }
+    */
+}
+
+fn print_array5_v2(a: &[i32; 5]) {
+    // x is &i32
+    for x in a {
+        println!("{x}")
+    }
+}
+
+fn double_array5(a: &mut [i32; 5]) {
+    /*
+     * this works
+        for i in 0..5 {
+            a[i] *= 2;
+        }
+    */
+
+    for x in a {
+        *x *= 2;
+    }
+}