revert "rm(strings)"

subjects/strings/README.md

@@ -0,0 +1,38 @@
+## strings
+
+### Instructions
+
+Create a **function** which receives a string slice and returns the number of characters in that string.
+
+### Expected Function
+
+```rust
+pub fn char_length(s: &str) -> usize {
+}
+```
+
+### Usage
+
+Here is a program to test your function.
+
+```rust
+use strings::*;
+
+fn main() {
+	println!("length of {} = {}", "❤", char_length("❤"));
+	println!("length of {} = {}", "形声字", char_length("形聲字"));
+	println!("length of {} = {}", "change", char_length("change"));
+	println!("length of {} = {}", "😍", char_length("😍"));
+}
+```
+
+And its output
+
+```console
+$ cargo run
+length of ❤ = 1
+length of 形声字 = 3
+length of change = 6
+length of 😍 = 1
+$
+```