adding "mut" and removing extra exercise

subjects/name_initials/README.md

@@ -27,7 +27,7 @@ Here is a program to test your function:
 use name_initials::initials;
 
 fn main() {
-    let names = vec!["Harry Potter", "Someone Else", "J. L.", "Barack Obama"]
+    let mut names = vec!["Harry Potter", "Someone Else", "J. L.", "Barack Obama"]
     println!("{:?}", initials(&mut names));
 }
 ```

subjects/string_literal/README.md

@@ -1,66 +0,0 @@
-## string literal
-
-### Instructions
-
-Create the following **functions**:
-
-- `is_empty`, which returns `true` if a string is empty
-- `is_ascii`, which returns `true` if all characters of a given string is in ASCII range
-- `contains`, which returns `true` if the string contains a given pattern
-- `split_at`, which divides a string in two returning a tuple
-- `find`, which returns the index if the first character of a given string which matches the pattern
-
-> This exercise will test the **heap allocation** of your function!
-> So try your best to allocate the minimum data on the heap! (hit: &str)
-
-### Notions
-
-- https://doc.rust-lang.org/1.22.0/book/first-edition/the-stack-and-the-heap.html
-- https://doc.rust-lang.org/rust-by-example/primitives/literals.html
-
-### Expected Functions
-
-```rust
-fn is_empty(v: &str) -> bool {
-}
-
-fn is_ascii(v: &str) -> bool {
-}
-
-fn contains(v: &str, pat: &str) -> bool {
-}
-
-fn split_at(v: &str, index: usize) -> (&str, &str) {
-}
-
-fn find(v: &str, pat: char) -> usize {
-}
-```
-
-### Usage
-
-Here is a program to test your function
-
-```rust
-use string_literal::*;
-
-fn main() {
-    println!("{}", is_empty(""));
-    println!("{}", is_ascii("rust"));
-    println!("{}", contains("rust", "ru"));
-    println!("{:?}", split_at("rust", 2));
-    println!("{}", find("rust", 'u'));
-}
-```
-
-And its output
-
-```console
-student@ubuntu:~/[[ROOT]]/test$ cargo run
-true
-true
-true
-("ru", "st")
-1
-student@ubuntu:~/[[ROOT]]/test$
-```

subjects/string_literals/README.md

@@ -42,12 +42,25 @@ fn find(v: &str, pat: char) -> usize {
 Here is a program to test your function
 
 ```rust
-
+use string_literal::*;
+
+fn main() {
+    println!("{}", is_empty(""));
+    println!("{}", is_ascii("rust"));
+    println!("{}", contains("rust", "ru"));
+    println!("{:?}", split_at("rust", 2));
+    println!("{}", find("rust", 'u'));
+}
 ```
 
 And its output
 
 ```console
 student@ubuntu:~/[[ROOT]]/test$ cargo run
+true
+true
+true
+("ru", "st")
+1
 student@ubuntu:~/[[ROOT]]/test$
 ```