add strings binary (episode 13)

Author: Byron

Cargo.lock

@@ -0,0 +1,8 @@
+[package]
+name = "strings"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

strings/Cargo.toml

@@ -0,0 +1,15 @@
+fn main() {
+    let s: &'static str = "hello😅👋🏼👋🏿你好";
+    for char in s.chars() {
+        println!("{}", char)
+    }
+    println!(
+        "{} = sizeof(char) ({} = MAX chars, unlike {} u32 MAX)",
+        std::mem::size_of::<char>(),
+        char::MAX as u32,
+        u32::MAX
+    );
+    println!("{:?}", &s[..9]);
+    s.to_owned().push('c');
+    s.to_owned().push_str("c");
+}