1 files changed, 87 insertions, 0 deletions
diff --git a/rust/theBook/chapter-8-common-collections/practice/src/main.rs b/rust/theBook/chapter-8-common-collections/practice/src/main.rs
new file mode 100644
index 0000000..ba63d64
--- /dev/null
+++ b/rust/theBook/chapter-8-common-collections/practice/src/main.rs
@@ -0,0 +1,87 @@
+use std::{{collections::HashMap as hm, io}};
+use rand::Rng;
+
+fn main() {
+    median();
+    pig_latin(&"appearance is the best".to_string());
+
+    add_emp();
+}
+
+fn median() {
+    // generate a list of number
+    let mut arr = Vec::new();
+    for _x in 0..100 {
+        let p = rand::thread_rng().gen_range(1..=10);
+        arr.push(p);
+    }
+
+    // count each number's appearance
+    let mut num_hash = hm::new();
+    for x in &arr {
+        let count = num_hash.entry(x).or_insert(0);
+        *count += 1;
+    }
+
+    // get most appearance
+    let mut key = 0;
+    let mut ret = 0;
+    for (k,v) in num_hash.iter() {
+        if *v > ret {
+            key = **k;
+            ret = *v;
+        }
+    }
+
+    println!("most appearance: {key} {ret}");
+}
+
+fn pig_latin(st: &String) {
+    let vowel = ['a', 'e', 'i', 'o', 'u'];
+    for w in st.split_whitespace() {
+        for v in vowel {
+            if w.starts_with(v) {
+                println!("{:?}",format!("{w}-hay"));
+                break;
+            }   else {
+                let pl = w.chars().nth(0).unwrap();
+                println!("{:?}",format!("{w}-{pl}ay"));
+                break;
+            }
+        }
+    }
+}
+
+fn add_emp() {
+    println!("Employee interface");
+
+    let mut hash: hm<String, Vec<String>> = hm::new();
+
+    loop {
+        let mut rd = String::new();
+        println!("enter name: ");
+        io::stdin()
+            .read_line(&mut rd)
+            .expect("failed to read line");
+
+        if rd.trim() == "q" {
+            break;
+        }
+
+        let mut wd = String::new();
+        println!("enter department: ");
+        io::stdin()
+            .read_line(&mut wd)
+            .expect("failed to read line");
+
+        if wd.trim() == "q" {
+            break;
+        }
+
+        hash.entry(wd).or_insert_with(Vec::new).push((*rd.trim()).to_string());
+    }
+
+    for (k,v) in &hash {
+        println!("{k} {:?}", v);
+    }
+}