diff --git a/docs/15_ko.html b/docs/15_ko.html
index e987c4c1d9dcb43131468db7a3404c7d685f3ae1..3d474a45727bb6cb28b03115998b07f94072a3a1 100644
--- a/docs/15_ko.html
+++ b/docs/15_ko.html
@@ -71,7 +71,7 @@ fn main() {
             </div>
             </div>
             <div class="code">
-            <iframe id="rust-playground" width="100%" src="https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&code=fn%20swap(x%3A%20i32%2C%20y%3A%20i32)%20-%3E%20(i32%2C%20i32)%20%7B%0A%20%20%20%20return%20(y%2C%20x)%3B%0A%7D%0A%0Afn%20main()%20%7B%0A%20%20%20%20%2F%2F%20return%20a%20tuple%20of%20return%20values%0A%20%20%20%20let%20result%20%3D%20swap(123%2C%20321)%3B%0A%20%20%20%20println!(%22%7B%7D%20%7B%7D%22%2C%20result.0%2C%20result.1)%3B%0A%0A%20%20%20%20%2F%2F%20destructure%20the%20tuple%20into%20two%20variables%20names%0A%20%20%20%20let%20(a%2C%20b)%20%3D%20swap(result.0%2C%20result.1)%3B%0A%20%20%20%20println!(%22%7B%7D%20%7B%7D%22%2C%20a%2C%20b)%3B%0A%7D%0A" scrolling="no" frameborder="no" allowtransparency="true" allowfullscreen="true" sandbox="allow-forms allow-pointer-lock allow-popups allow-same-origin allow-scripts allow-modals" title="Rust Playground" loading="lazy"></iframe>
+            <iframe id="rust-playground" width="100%" src="https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&code=%2F%2F+%EC%97%B4%EA%B1%B0%ED%98%95+%EC%A0%95%EC%9D%98%3A+%EC%97%AC%EB%9F%AC+%EB%8F%84%ED%98%95%EC%9D%84+%EB%82%98%ED%83%80%EB%83%85%EB%8B%88%EB%8B%A4.%0Aenum+Shape+%7B%0A++++Circle+%7B+radius%3A+f64+%7D%2C%0A++++Square+%7B+side%3A+f64+%7D%2C%0A++++Rectangle+%7B+width%3A+f64%2C+height%3A+f64+%7D%2C%0A%7D%0A%0A%2F%2F+%EB%8F%84%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%EB%A5%BC+%EA%B3%84%EC%82%B0%ED%95%98%EB%8A%94+%ED%95%A8%EC%88%98%0Afn+calculate_area%28shape%3A+Shape%29+-%3E+f64+%7B%0A++++%2F%2F+%ED%8C%A8%ED%84%B4+%EB%A7%A4%EC%B9%AD%EC%9D%84+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8F%84%ED%98%95%EC%9D%98+%EC%A2%85%EB%A5%98%EC%97%90+%EB%94%B0%EB%9D%BC+%EA%B3%84%EC%82%B0+%EB%B0%A9%EC%8B%9D%EC%9D%84+%EC%84%A0%ED%83%9D%ED%95%A9%EB%8B%88%EB%8B%A4.%0A++++match+shape+%7B%0A++++++++Shape%3A%3ACircle+%7B+radius+%7D+%3D%3E+std%3A%3Af64%3A%3Aconsts%3A%3API+*+radius+*+radius%2C+%2F%2F+%EC%9B%90%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++++++Shape%3A%3ASquare+%7B+side+%7D+%3D%3E+side+*+side%2C++++++++++++++++++++++++++++++%2F%2F+%EC%A0%95%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++++++Shape%3A%3ARectangle+%7B+width%2C+height+%7D+%3D%3E+width+*+height%2C+++++++++++++++%2F%2F+%EC%A7%81%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++%7D%0A%7D%0A%0Afn+main%28%29+%7B%0A++++%2F%2F+%EC%97%AC%EB%9F%AC+%EB%8F%84%ED%98%95+%EC%83%9D%EC%84%B1%0A++++let+circle+%3D+Shape%3A%3ACircle+%7B+radius%3A+5.0+%7D%3B%0A++++let+square+%3D+Shape%3A%3ASquare+%7B+side%3A+4.0+%7D%3B%0A++++let+rectangle+%3D+Shape%3A%3ARectangle+%7B%0A++++++++width%3A+6.0%2C%0A++++++++height%3A+3.0%2C%0A++++%7D%3B%0A%0A++++%2F%2F+%ED%8C%A8%ED%84%B4+%EB%A7%A4%EC%B9%AD%EC%9D%84+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EA%B0%81+%EB%8F%84%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%EB%A5%BC+%EA%B3%84%EC%82%B0%ED%95%98%EA%B3%A0+%EC%B6%9C%EB%A0%A5%ED%95%A9%EB%8B%88%EB%8B%A4.%0A++++let+circle_area+%3D+calculate_area%28circle%29%3B%0A++++let+square_area+%3D+calculate_area%28square%29%3B%0A++++let+rectangle_area+%3D+calculate_area%28rectangle%29%3B%0A%0A++++println%21%28%22%EC%9B%90%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+circle_area%29%3B%0A++++println%21%28%22%EC%A0%95%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+square_area%29%3B%0A++++println%21%28%22%EC%A7%81%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+rectangle_area%29%3B%0A%7D%0A" scrolling="no" frameborder="no" allowtransparency="true" allowfullscreen="true" sandbox="allow-forms allow-pointer-lock allow-popups allow-same-origin allow-scripts allow-modals" title="Rust Playground" loading="lazy"></iframe>
             </div>
         </div>
         <!-- <script>
diff --git a/docs/19_ko.html b/docs/19_ko.html
index 6dc6c3dd07d1d308f04f89c2446e2ec65a8611b7..e566377106ae9186ee16bddf99a2ad5844c6df1c 100644
--- a/docs/19_ko.html
+++ b/docs/19_ko.html
@@ -50,7 +50,9 @@
                 <span class="next"><a href="chapter_2_ko.html" rel="next">다음 ❯</a></span>
             </div>
             </div>
-            <div class="code"><center><img src="/ferris_lofi.png" alt="Rust Tutorial" width="300" height="100%"></center></div>
+            <div class="code">
+            <iframe id="rust-playground" width="100%" src="https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&code=%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%2C+%EB%B9%8C%EB%A6%BC%2C+%EC%B0%B8%EC%A1%B0%2C+%EB%B2%94%EC%9C%84+%EB%93%B1%EC%9D%98+%EA%B8%B0%EB%8A%A5%EC%9D%84+%ED%95%9C+%EB%B2%88%EC%97%90+%EC%82%AC%EC%9A%A9%0D%0A%23%5Bderive%28Debug%29%5D%0D%0Astruct+MyStruct+%7B%0D%0A++++data%3A+String%2C%0D%0A%7D%0D%0A%0D%0Afn+print_and_modify%28s%3A+%26mut+MyStruct%29+%7B%0D%0A++++println%21%28%22%5Ct%3E+MyStruct%EB%A5%BC+%EC%B0%B8%EC%A1%B0%3A+%7B%3A%3F%7D%22%2C+s%29%3B%0D%0A++++s.data.push_str%28%22+%EC%88%98%EC%A0%95%EB%90%A8%22%29%3B%0D%0A%7D%0D%0A%0D%0Afn+main%28%29+%7B%0D%0A++++let+mut+my_struct1+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct1%22%29%2C%0D%0A++++%7D%3B%0D%0A%0D%0A++++let+mut+my_struct2+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct2%22%29%2C%0D%0A++++%7D%3B%0D%0A%0D%0A++++%2F%2F+%EB%B6%88%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8D%B0%EC%9D%B4%ED%84%B0%EB%A5%BC+%EC%B6%9C%EB%A0%A5%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EB%B6%88%EB%B3%80+%EC%B0%B8%EC%A1%B0%3A+%7B%3A%3F%7D%22%2C+%26my_struct1%29%3B%0D%0A%0D%0A++++%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8D%B0%EC%9D%B4%ED%84%B0%EB%A5%BC+%EC%88%98%EC%A0%95%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++print_and_modify%28%26mut+my_struct1%29%3B%0D%0A++++println%21%28%22%EC%88%98%EC%A0%95%EB%90%9C+MyStruct1%3A+%7B%3A%3F%7D%22%2C+my_struct1%29%3B%0D%0A%0D%0A++++%2F%2F+%EB%B2%94%EC%9C%84%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%B9%8C%EB%A6%BC%EC%9D%98+%EA%B7%9C%EC%B9%99%EC%9D%84+%EB%B3%B4%EC%97%AC%EC%A4%8D%EB%8B%88%EB%8B%A4.%0D%0A++++%7B%0D%0A++++++++let+mut_ref+%3D+%26mut+my_struct2%3B+%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%83%9D%EC%84%B1%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++++++print_and_modify%28mut_ref%29%3B+%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%ED%95%A8%EC%88%98%EC%97%90+%EC%A0%84%EB%8B%AC%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++++++%2F%2F+%EC%9D%B4+%EC%A7%80%EC%A0%90%EC%97%90%EC%84%9C+mut_ref%EB%A5%BC+%EB%8D%94+%EC%9D%B4%EC%83%81+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%97%86%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++%7D%0D%0A%0D%0A++++%2F%2F+%EB%B2%94%EC%9C%84%EB%A5%BC+%EB%B2%97%EC%96%B4%EB%82%9C+%ED%9B%84%EC%97%90%EB%8A%94+%EC%9B%90%EB%9E%98+%EB%B3%80%EC%88%98%EB%A5%BC+%EB%8B%A4%EC%8B%9C+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%9E%88%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EC%88%98%EC%A0%95%EB%90%9C+MyStruct2%3A+%7B%3A%3F%7D%22%2C+my_struct2%29%3B%0D%0A%0D%0A++++%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%84+%EC%9D%B4%EB%8F%99%EC%8B%9C%ED%82%B5%EB%8B%88%EB%8B%A4.%0D%0A++++let+my_struct3+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct3%22%29%2C%0D%0A++++%7D%3B%0D%0A++++let+my_struct4+%3D+my_struct3%3B+%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%84+%EC%9D%B4%EB%8F%99%EC%8B%9C%ED%82%B5%EB%8B%88%EB%8B%A4.%0D%0A++++%2F%2F+%EC%9D%B4%EC%A0%9C+my_struct3%EC%9D%80+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%97%86%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%B4+%EC%9D%B4%EB%8F%99%EB%90%9C+MyStruct4%3A+%7B%3A%3F%7D%22%2C+my_struct4%29%3B%0D%0A%7D%0D%0A" scrolling="no" frameborder="no" allowtransparency="true" allowfullscreen="true" sandbox="allow-forms allow-pointer-lock allow-popups allow-same-origin allow-scripts allow-modals" title="Rust Playground" loading="lazy"></iframe>
+            </div>
         </div>
         <!-- <script>
           document.addEventListener("DOMContentLoaded", function() {
diff --git a/docs/tour.js b/docs/tour.js
index ff1e295d260d631fad0cd2bb843544ece9501dc9..8ac68098c300d7deeb996b6b17b1f5c016eaed7e 100644
--- a/docs/tour.js
+++ b/docs/tour.js
@@ -1,105 +1,68 @@
 const triggerLinkClick = direction => {
   const link = document.querySelector(`.${direction} a`);
-  if (link) {
-    link.click();
-  }
+  link && link.click();
 };
 
-var xDown = null;
-var yDown = null;
-
-const handleTouchStart = evt => {
-  xDown = evt.touches[0].clientX;
-  yDown = evt.touches[0].clientY;
+const handleTouchStart = ({ touches }) => {
+  [xDown, yDown] = [touches[0].clientX, touches[0].clientY];
 };
 
-const handleTouchMove = evt => {
-  if (!xDown || !yDown) {
-    return;
-  }
+const handleTouchMove = ({ touches, target }) => {
+  if (!xDown || !yDown) return;
 
-  var touchTarget = evt.target;
+  let touchTarget = target;
   while (touchTarget) {
-    if (
-      touchTarget.tagName === "CODE" &&
-      touchTarget.parentElement.tagName === "PRE"
-    ) {
-      // ignore swipe on pre > code elements
-      return;
-    }
-    touchTarget = touchTarget.parentElement;
+    const { tagName, parentElement } = touchTarget;
+    if (tagName === "CODE" && parentElement.tagName === "PRE") return;
+    touchTarget = parentElement;
   }
 
-  var xUp = evt.touches[0].clientX;
-  var yUp = evt.touches[0].clientY;
-
-  var xDiff = xDown - xUp;
-  var yDiff = yDown - yUp;
+  const [xUp, yUp] = [touches[0].clientX, touches[0].clientY];
+  const [xDiff, yDiff] = [xDown - xUp, yDown - yUp];
   if (Math.abs(xDiff) + Math.abs(yDiff) > 100) {
     if (Math.abs(xDiff) > Math.abs(yDiff)) {
-      if (xDiff > 0) {
-        /* left swipe */
-        triggerLinkClick("next");
-      } else {
-        /* right swipe */
-        triggerLinkClick("back");
-      }
+      triggerLinkClick(xDiff > 0 ? "next" : "back");
     }
-    /* reset values */
-    xDown = null;
-    yDown = null;
+    [xDown, yDown] = [null, null];
   }
 };
 
-let activeEl = null;
-document.addEventListener(
-  "focus",
-  event => {
-    activeEl = event.target;
-  },
-  true
-);
+const onKeyUp = e => {
+  if (e.ctrlKey || e.altKey || e.metaKey || e.shiftKey) return;
 
-const setupKeys = () => {
-  // PC
-  document.body.addEventListener("keyup", e => {
-    if (e.ctrlKey || e.altKey || e.metaKey || e.shiftKey) {
-      return;
-    }
+  // const { tagName } = document.activeElement;
+  // if (tagName === "SPAN") return;
 
-    if (document.activeElement.tagName === "SPAN") {
-      // ignore keys on pre > code elements
+  const hasScrollableParent = el => el.scrollWidth > el.clientWidth;
+  let el = document.activeElement;
+  while (el && el !== document.body) {
+    if (hasScrollableParent(el) && el.tagName !== "A") {
+      e.preventDefault();
       return;
     }
+    el = el.parentElement;
+  }
 
-    // check if the active element has a scrollable parent
-    const hasScrollableParent = el => el.scrollWidth > el.clientWidth;
-    let el = document.activeElement;
-    while (el) {
-      if (el === document.body) {
-        break; // stop checking if we reach the body element
-      }
-      if (hasScrollableParent(el) && el.tagName !== "A") {
-        e.preventDefault();
-        return;
-      }
-      el = el.parentElement;
-    }
+  const { key } = e;
+  if (key === "Right" || key === "ArrowRight") {
+    triggerLinkClick("next");
+  } else if (key === "Left" || key === "ArrowLeft") {
+    triggerLinkClick("back");
+  }
+};
 
-    if (e.key === "Right" || e.key === "ArrowRight") {
-      triggerLinkClick("next");
-    }
-    if (e.key === "Left" || e.key === "ArrowLeft") {
-      triggerLinkClick("back");
-    }
-  });
+const setupKeys = () => {
+  document.body.addEventListener("keyup", onKeyUp);
 };
 
+// document.addEventListener("focus", ({ target }) => {
+//   activeEl = target;
+// }, true);
+
 document.addEventListener("touchstart", handleTouchStart, false);
 document.addEventListener("touchmove", handleTouchMove, false);
 setupKeys();
 
-// in iframe, should not be same
 const iframeElement = document.querySelector("iframe");
 if (iframeElement) {
   setupKeys();
diff --git a/frontend/lessons/ko/chapter_1.yaml b/frontend/lessons/ko/chapter_1.yaml
index 8c0e32b22a5bd45f77e0b679aab3a8e300dd7700..26d04df574d040b419bf7949a7c0eacb7e2acfd3 100644
--- a/frontend/lessons/ko/chapter_1.yaml
+++ b/frontend/lessons/ko/chapter_1.yaml
@@ -220,7 +220,7 @@
     우리는 더 많은 형태로 볼 것이며, 이를 통해 데이터 구조의 하위 요소를 직관적으로 추출할 수 있습니다.
 - title: match
   code: >-
-    https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&code=fn%20swap(x%3A%20i32%2C%20y%3A%20i32)%20-%3E%20(i32%2C%20i32)%20%7B%0A%20%20%20%20return%20(y%2C%20x)%3B%0A%7D%0A%0Afn%20main()%20%7B%0A%20%20%20%20%2F%2F%20return%20a%20tuple%20of%20return%20values%0A%20%20%20%20let%20result%20%3D%20swap(123%2C%20321)%3B%0A%20%20%20%20println!(%22%7B%7D%20%7B%7D%22%2C%20result.0%2C%20result.1)%3B%0A%0A%20%20%20%20%2F%2F%20destructure%20the%20tuple%20into%20two%20variables%20names%0A%20%20%20%20let%20(a%2C%20b)%20%3D%20swap(result.0%2C%20result.1)%3B%0A%20%20%20%20println!(%22%7B%7D%20%7B%7D%22%2C%20a%2C%20b)%3B%0A%7D%0A
+    https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&code=%2F%2F+%EC%97%B4%EA%B1%B0%ED%98%95+%EC%A0%95%EC%9D%98%3A+%EC%97%AC%EB%9F%AC+%EB%8F%84%ED%98%95%EC%9D%84+%EB%82%98%ED%83%80%EB%83%85%EB%8B%88%EB%8B%A4.%0Aenum+Shape+%7B%0A++++Circle+%7B+radius%3A+f64+%7D%2C%0A++++Square+%7B+side%3A+f64+%7D%2C%0A++++Rectangle+%7B+width%3A+f64%2C+height%3A+f64+%7D%2C%0A%7D%0A%0A%2F%2F+%EB%8F%84%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%EB%A5%BC+%EA%B3%84%EC%82%B0%ED%95%98%EB%8A%94+%ED%95%A8%EC%88%98%0Afn+calculate_area%28shape%3A+Shape%29+-%3E+f64+%7B%0A++++%2F%2F+%ED%8C%A8%ED%84%B4+%EB%A7%A4%EC%B9%AD%EC%9D%84+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8F%84%ED%98%95%EC%9D%98+%EC%A2%85%EB%A5%98%EC%97%90+%EB%94%B0%EB%9D%BC+%EA%B3%84%EC%82%B0+%EB%B0%A9%EC%8B%9D%EC%9D%84+%EC%84%A0%ED%83%9D%ED%95%A9%EB%8B%88%EB%8B%A4.%0A++++match+shape+%7B%0A++++++++Shape%3A%3ACircle+%7B+radius+%7D+%3D%3E+std%3A%3Af64%3A%3Aconsts%3A%3API+*+radius+*+radius%2C+%2F%2F+%EC%9B%90%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++++++Shape%3A%3ASquare+%7B+side+%7D+%3D%3E+side+*+side%2C++++++++++++++++++++++++++++++%2F%2F+%EC%A0%95%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++++++Shape%3A%3ARectangle+%7B+width%2C+height+%7D+%3D%3E+width+*+height%2C+++++++++++++++%2F%2F+%EC%A7%81%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4+%EA%B3%84%EC%82%B0%0A++++%7D%0A%7D%0A%0Afn+main%28%29+%7B%0A++++%2F%2F+%EC%97%AC%EB%9F%AC+%EB%8F%84%ED%98%95+%EC%83%9D%EC%84%B1%0A++++let+circle+%3D+Shape%3A%3ACircle+%7B+radius%3A+5.0+%7D%3B%0A++++let+square+%3D+Shape%3A%3ASquare+%7B+side%3A+4.0+%7D%3B%0A++++let+rectangle+%3D+Shape%3A%3ARectangle+%7B%0A++++++++width%3A+6.0%2C%0A++++++++height%3A+3.0%2C%0A++++%7D%3B%0A%0A++++%2F%2F+%ED%8C%A8%ED%84%B4+%EB%A7%A4%EC%B9%AD%EC%9D%84+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EA%B0%81+%EB%8F%84%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%EB%A5%BC+%EA%B3%84%EC%82%B0%ED%95%98%EA%B3%A0+%EC%B6%9C%EB%A0%A5%ED%95%A9%EB%8B%88%EB%8B%A4.%0A++++let+circle_area+%3D+calculate_area%28circle%29%3B%0A++++let+square_area+%3D+calculate_area%28square%29%3B%0A++++let+rectangle_area+%3D+calculate_area%28rectangle%29%3B%0A%0A++++println%21%28%22%EC%9B%90%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+circle_area%29%3B%0A++++println%21%28%22%EC%A0%95%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+square_area%29%3B%0A++++println%21%28%22%EC%A7%81%EC%82%AC%EA%B0%81%ED%98%95%EC%9D%98+%EB%84%93%EC%9D%B4%3A+%7B%7D%22%2C+rectangle_area%29%3B%0A%7D%0A
   content_markdown: >
     Rust에서 match 키워드는 패턴 매칭을 위해 사용하고
 
@@ -464,8 +464,8 @@
   content_markdown: >
     Error handling
 - title: Chapter 1 - 마무리
-  source: >-
-    /ferris_lofi.png
+  code: >-
+    https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&code=%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%2C+%EB%B9%8C%EB%A6%BC%2C+%EC%B0%B8%EC%A1%B0%2C+%EB%B2%94%EC%9C%84+%EB%93%B1%EC%9D%98+%EA%B8%B0%EB%8A%A5%EC%9D%84+%ED%95%9C+%EB%B2%88%EC%97%90+%EC%82%AC%EC%9A%A9%0D%0A%23%5Bderive%28Debug%29%5D%0D%0Astruct+MyStruct+%7B%0D%0A++++data%3A+String%2C%0D%0A%7D%0D%0A%0D%0Afn+print_and_modify%28s%3A+%26mut+MyStruct%29+%7B%0D%0A++++println%21%28%22%5Ct%3E+MyStruct%EB%A5%BC+%EC%B0%B8%EC%A1%B0%3A+%7B%3A%3F%7D%22%2C+s%29%3B%0D%0A++++s.data.push_str%28%22+%EC%88%98%EC%A0%95%EB%90%A8%22%29%3B%0D%0A%7D%0D%0A%0D%0Afn+main%28%29+%7B%0D%0A++++let+mut+my_struct1+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct1%22%29%2C%0D%0A++++%7D%3B%0D%0A%0D%0A++++let+mut+my_struct2+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct2%22%29%2C%0D%0A++++%7D%3B%0D%0A%0D%0A++++%2F%2F+%EB%B6%88%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8D%B0%EC%9D%B4%ED%84%B0%EB%A5%BC+%EC%B6%9C%EB%A0%A5%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EB%B6%88%EB%B3%80+%EC%B0%B8%EC%A1%B0%3A+%7B%3A%3F%7D%22%2C+%26my_struct1%29%3B%0D%0A%0D%0A++++%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%8D%B0%EC%9D%B4%ED%84%B0%EB%A5%BC+%EC%88%98%EC%A0%95%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++print_and_modify%28%26mut+my_struct1%29%3B%0D%0A++++println%21%28%22%EC%88%98%EC%A0%95%EB%90%9C+MyStruct1%3A+%7B%3A%3F%7D%22%2C+my_struct1%29%3B%0D%0A%0D%0A++++%2F%2F+%EB%B2%94%EC%9C%84%EB%A5%BC+%EC%82%AC%EC%9A%A9%ED%95%98%EC%97%AC+%EB%B9%8C%EB%A6%BC%EC%9D%98+%EA%B7%9C%EC%B9%99%EC%9D%84+%EB%B3%B4%EC%97%AC%EC%A4%8D%EB%8B%88%EB%8B%A4.%0D%0A++++%7B%0D%0A++++++++let+mut_ref+%3D+%26mut+my_struct2%3B+%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%EC%83%9D%EC%84%B1%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++++++print_and_modify%28mut_ref%29%3B+%2F%2F+%EA%B0%80%EB%B3%80+%EC%B0%B8%EC%A1%B0%EB%A5%BC+%ED%95%A8%EC%88%98%EC%97%90+%EC%A0%84%EB%8B%AC%ED%95%A9%EB%8B%88%EB%8B%A4.%0D%0A++++++++%2F%2F+%EC%9D%B4+%EC%A7%80%EC%A0%90%EC%97%90%EC%84%9C+mut_ref%EB%A5%BC+%EB%8D%94+%EC%9D%B4%EC%83%81+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%97%86%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++%7D%0D%0A%0D%0A++++%2F%2F+%EB%B2%94%EC%9C%84%EB%A5%BC+%EB%B2%97%EC%96%B4%EB%82%9C+%ED%9B%84%EC%97%90%EB%8A%94+%EC%9B%90%EB%9E%98+%EB%B3%80%EC%88%98%EB%A5%BC+%EB%8B%A4%EC%8B%9C+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%9E%88%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EC%88%98%EC%A0%95%EB%90%9C+MyStruct2%3A+%7B%3A%3F%7D%22%2C+my_struct2%29%3B%0D%0A%0D%0A++++%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%84+%EC%9D%B4%EB%8F%99%EC%8B%9C%ED%82%B5%EB%8B%88%EB%8B%A4.%0D%0A++++let+my_struct3+%3D+MyStruct+%7B%0D%0A++++++++data%3A+String%3A%3Afrom%28%22MyStruct3%22%29%2C%0D%0A++++%7D%3B%0D%0A++++let+my_struct4+%3D+my_struct3%3B+%2F%2F+%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%84+%EC%9D%B4%EB%8F%99%EC%8B%9C%ED%82%B5%EB%8B%88%EB%8B%A4.%0D%0A++++%2F%2F+%EC%9D%B4%EC%A0%9C+my_struct3%EC%9D%80+%EC%82%AC%EC%9A%A9%ED%95%A0+%EC%88%98+%EC%97%86%EC%8A%B5%EB%8B%88%EB%8B%A4.%0D%0A++++println%21%28%22%EC%86%8C%EC%9C%A0%EA%B6%8C%EC%9D%B4+%EC%9D%B4%EB%8F%99%EB%90%9C+MyStruct4%3A+%7B%3A%3F%7D%22%2C+my_struct4%29%3B%0D%0A%7D%0D%0A
   content_markdown: >
     Rust의 기초는 그렇게 나쁘지 않죠?