encode-and-decode-strings (#2769)

Author: DaleSeo

encode-and-decode-strings/DaleSeo.rs

@@ -0,0 +1,22 @@
+// TC: O(n)
+// SC: O(n)
+impl Solution {
+    pub fn encode(strs: Vec<String>) -> String {
+        strs.iter()
+            .map(|s| format!("{}#{}", s.len(), s))
+            .collect()
+    }
+
+    pub fn decode(s: String) -> Vec<String> {
+        let mut strs = Vec::new();
+        let bytes = s.as_bytes();
+        let mut i = 0;
+        while i < bytes.len() {
+            let sep = s[i..].find('#').unwrap() + i;
+            let len: usize = s[i..sep].parse().unwrap();
+            strs.push(s[sep + 1..sep + 1 + len].to_string());
+            i = sep + 1 + len;
+        }
+        strs
+    }
+}