diff --git a/problem-1/01-bubble-sort.png b/problem-1/01-bubble-sort.png
new file mode 100644
index 0000000..0a2b9a8
Binary files /dev/null and b/problem-1/01-bubble-sort.png differ
diff --git a/problem-1/README.md b/problem-1/README.md
index 99c4ed7..240e6bd 100644
--- a/problem-1/README.md
+++ b/problem-1/README.md
@@ -14,6 +14,8 @@
 ```
 
 2. 버블 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
+![01-bubble-sort.png](01-bubble-sort.png)
+
 
 3. 버블 정렬의 코드를 직접 구현해 주세요.
 
diff --git a/problem-1/problem-1.test.js b/problem-1/problem-1.test.js
index f54f840..0235fe6 100644
--- a/problem-1/problem-1.test.js
+++ b/problem-1/problem-1.test.js
@@ -1,4 +1,26 @@
+const exchange = (array, index1, index2) => {
+  [array[index1], array[index2]] = [array[index2], array[index1]];
+};
+
+const isFirstBiggerThanSecond = (a, b) => a > b;
 const bubbleSort = (array) => {
+  const { length } = array;
+
+  for (let pass = 1; pass <= length; pass++) {
+    let exchangeCount = 0;
+
+    for (let index = 0; index < length - pass; index++) {
+      if (isFirstBiggerThanSecond(array[index], array[index + 1])) {
+        exchange(array, index, index + 1);
+        exchangeCount++;
+      }
+    }
+
+    // todo : 정렬이 완료됐다면 loop 를 종료한다.
+    if (exchangeCount === 0) {
+      break;
+    }
+  }
 };
 
 test.each([
diff --git a/problem-2/02-selection-sort.jpeg b/problem-2/02-selection-sort.jpeg
new file mode 100644
index 0000000..058254a
Binary files /dev/null and b/problem-2/02-selection-sort.jpeg differ
diff --git a/problem-2/README.md b/problem-2/README.md
index a5996a6..9f139db 100644
--- a/problem-2/README.md
+++ b/problem-2/README.md
@@ -13,5 +13,7 @@
 ```
 
 2. 선택 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
+![02-selection-sort.jpeg](02-selection-sort.jpeg)
+
 
 3. 선택 정렬의 코드를 직접 구현해 주세요.
diff --git a/problem-2/problem-2.test.js b/problem-2/problem-2.test.js
index 1e1fe4f..53a864a 100644
--- a/problem-2/problem-2.test.js
+++ b/problem-2/problem-2.test.js
@@ -1,4 +1,27 @@
+const exchange = (array, index1, index2) => {
+  [array[index1], array[index2]] = [array[index2], array[index1]];
+};
+
+const isFirstLesserThanSecond = (a, b) => a < b;
+
+const findMinValueIndex = (array, startIndex) => {
+  let minValueIndex = startIndex;
+
+  for (let index = startIndex + 1; index < array.length; index++) {
+    if (isFirstLesserThanSecond(array[index], array[minValueIndex])) {
+      minValueIndex = index;
+    }
+  }
+
+  return minValueIndex;
+};
+
 const selectionSort = (array) => {
+  for (let index = 0; index < array.length - 1; index++) {
+    const minValueIndex = findMinValueIndex(array, index);
+
+    exchange(array, index, minValueIndex);
+  }
 };
 
 test.each([
diff --git a/problem-3/03-insertion-sort.png b/problem-3/03-insertion-sort.png
new file mode 100644
index 0000000..9441431
Binary files /dev/null and b/problem-3/03-insertion-sort.png differ
diff --git a/problem-3/README.md b/problem-3/README.md
index 02ba68a..ca1090d 100644
--- a/problem-3/README.md
+++ b/problem-3/README.md
@@ -13,5 +13,7 @@
 ```
 
 2. 삽입 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
+![03-insertion-sort.png](03-insertion-sort.png)
+
 
 3. 삽입 정렬의 코드를 직접 구현해 주세요.
diff --git a/problem-3/problem-3.test.js b/problem-3/problem-3.test.js
index e4450b5..a645225 100644
--- a/problem-3/problem-3.test.js
+++ b/problem-3/problem-3.test.js
@@ -1,4 +1,19 @@
+const exchange = (array, index1, index2) => {
+  [array[index1], array[index2]] = [array[index2], array[index1]];
+};
+
+const isFirstLesserThanSecond = (a, b) => a < b;
 const insertionSort = (array) => {
+  for (let currentIndex = 1; currentIndex < array.length; currentIndex++) {
+    for (let comparisonIndex = currentIndex; comparisonIndex > 0; comparisonIndex--) {
+      if (isFirstLesserThanSecond(array[comparisonIndex], array[comparisonIndex - 1])) {
+        exchange(array, comparisonIndex, comparisonIndex - 1);
+      } else {
+        // todo: 비교했을 때 왼쪽보다 작지 않다면 비교를 중지하고, 다음 index 로 넘어간다.
+        break;
+      }
+    }
+  }
 };
 
 test.each([
diff --git a/problem-4/04-shell-sort.png b/problem-4/04-shell-sort.png
new file mode 100644
index 0000000..ae8b44a
Binary files /dev/null and b/problem-4/04-shell-sort.png differ
diff --git a/problem-4/problem-4.test.js b/problem-4/problem-4.test.js
index 069ccdf..7bc2e99 100644
--- a/problem-4/problem-4.test.js
+++ b/problem-4/problem-4.test.js
@@ -1,4 +1,27 @@
+const exchange = (array, index1, index2) => {
+  [array[index1], array[index2]] = [array[index2], array[index1]];
+};
+
+const isFirstLesserThanSecond = (a, b) => a < b;
+
 const shellSort = (array) => {
+  const { length } = array;
+
+  let gap = Math.floor(length / 2);
+
+  while (gap > 0) {
+    for (let index = gap; index < length; index++) {
+      for (let previousIndex = index; previousIndex >= 0; previousIndex = previousIndex - gap) {
+        if (isFirstLesserThanSecond(array[previousIndex], array[previousIndex - gap])) {
+          exchange(array, previousIndex, previousIndex - gap);
+        } else {
+          break;
+        }
+      }
+    }
+
+    gap = Math.floor(gap / 2);
+  }
 };
 
 test.each([
diff --git a/problem-5/05-merge-sort-01.png b/problem-5/05-merge-sort-01.png
new file mode 100644
index 0000000..f1f78a3
Binary files /dev/null and b/problem-5/05-merge-sort-01.png differ
diff --git a/problem-5/06-merge-sort-02.jpeg b/problem-5/06-merge-sort-02.jpeg
new file mode 100644
index 0000000..7b2429d
Binary files /dev/null and b/problem-5/06-merge-sort-02.jpeg differ
diff --git a/problem-5/README.md b/problem-5/README.md
index 01799bb..e11b4b9 100644
--- a/problem-5/README.md
+++ b/problem-5/README.md
@@ -12,5 +12,6 @@
 ```
 
 2. 머지 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
-
+![05-merge-sort-01.png](05-merge-sort-01.png)
+![06-merge-sort-02.jpeg](06-merge-sort-02.jpeg)
 3. 머지 정렬의 코드를 직접 구현해 주세요.
diff --git a/problem-5/merge-sort-bottomUp.js b/problem-5/merge-sort-bottomUp.js
index a5425b1..1072a8d 100644
--- a/problem-5/merge-sort-bottomUp.js
+++ b/problem-5/merge-sort-bottomUp.js
@@ -1,20 +1,5 @@
 const less = (a, b) => a < b;
 
-const mergeSortBottomUp = (list) => {
-  const { length } = list;
-
-  for (let n = 1; n < length; n = n * 2) {
-    for (let start = 0; start < length - n; start = start + n * 2) {
-      merge(
-        list,
-        start,
-        start + (n - 1),
-        Math.min(start + ((n * 2) - 1), length - 1),
-      );
-    }
-  }
-};
-
 const merge = (list, start, mid, end) => {
   let left = start;
   let right = mid + 1;
@@ -37,6 +22,20 @@ const merge = (list, start, mid, end) => {
     }
   }
 };
+const mergeSortBottomUp = (list) => {
+  const { length } = list;
+
+  for (let n = 1; n < length; n = n * 2) {
+    for (let start = 0; start < length - n; start = start + n * 2) {
+      merge(
+        list,
+        start,
+        start + (n - 1),
+        Math.min(start + ((n * 2) - 1), length - 1),
+      );
+    }
+  }
+};
 
 module.exports = {
   mergeSortBottomUp,
diff --git a/problem-5/merge-sort.js b/problem-5/merge-sort.js
index fe56505..86ee617 100644
--- a/problem-5/merge-sort.js
+++ b/problem-5/merge-sort.js
@@ -1,17 +1,5 @@
 const less = (a, b) => a < b;
 
-const mergeSort = (list, start = 0, end = list.length - 1) => {
-  if (start >= end) {
-    return;
-  }
-
-  const mid = Math.floor((start + end) / 2);
-
-  mergeSort(list, start, mid);
-  mergeSort(list, mid + 1, end);
-  merge(list, start, mid, end);
-};
-
 const merge = (list, start, mid, end) => {
   let left = start;
   let right = mid + 1;
@@ -34,6 +22,17 @@ const merge = (list, start, mid, end) => {
     }
   }
 };
+const mergeSort = (list, start = 0, end = list.length - 1) => {
+  if (start >= end) {
+    return;
+  }
+
+  const mid = Math.floor((start + end) / 2);
+
+  mergeSort(list, start, mid);
+  mergeSort(list, mid + 1, end);
+  merge(list, start, mid, end);
+};
 
 module.exports = {
   mergeSort,
diff --git a/problem-5/problem-5.test.js b/problem-5/problem-5.test.js
index 124ce9e..3f44e6b 100644
--- a/problem-5/problem-5.test.js
+++ b/problem-5/problem-5.test.js
@@ -1,4 +1,39 @@
-const mergeSort = (array) => {
+const isFirstLesserThanSecond = (a, b) => a < b;
+const merge = (list, start, mid, end) => {
+  let left = start;
+  let right = mid + 1;
+
+  const temp = [...list];
+
+  for (let index = start; index <= end; index++) {
+    if (left > mid) { // 왼쪽의 정렬이 모두 끝났는가? -> 오른쪽 항목들을 채운다.
+      list[index] = temp[right];
+      right++;
+    } else if (right > end) { // 오른쪽의 정렬이 모두 끝났는가? -> 왼쪽 항목들을 채운다.
+      list[index] = temp[left];
+      left++;
+    } else if (isFirstLesserThanSecond(temp[left], temp[right])) {
+      // 왼쪽과 오른쪽의 항목 중 왼쪽 값이 더 작으면 넣는다.
+      list[index] = temp[left];
+      left++;
+    } else {
+      // 왼쪽과 오른쪽의 항목 중 오른쪽 값이 더 작으면 넣는다.
+      list[index] = temp[right];
+      right++;
+    }
+  }
+};
+
+const mergeSort = (list, start = 0, end = list.length - 1) => {
+  if (start >= end) {
+    return;
+  }
+
+  const mid = Math.floor((start + end) / 2);
+
+  mergeSort(list, start, mid); // 절반으로 나눈 왼쪽 리스트를 정렬
+  mergeSort(list, mid + 1, end); // 절반으로 나눈 오른쪽 리스트를 정렬
+  merge(list, start, mid, end);
 };
 
 test.each([
diff --git a/problem-6/README.md b/problem-6/README.md
index 67c9f36..08f57e9 100644
--- a/problem-6/README.md
+++ b/problem-6/README.md
@@ -14,5 +14,13 @@
 ```
 
 2. 퀵 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
+![quick-sort-code-01.png](quick-sort-code-01.png)
+![quick-sort-code-02.png](quick-sort-code-02.png)
+![quick-sort-code-03.png](quick-sort-code-03.png)
+![quick-sort-code-04.png](quick-sort-code-04.png)
+![quick-sort-code-05.png](quick-sort-code-05.png)
+![quick-sort-code-06.png](quick-sort-code-06.png)
+![quick-sort-code-07.png](quick-sort-code-07.png)
+![quick-sort-code-08.png](quick-sort-code-08.png)
 
 3. 퀵 정렬의 코드를 직접 구현해 주세요.
diff --git a/problem-6/problem-6.test.js b/problem-6/problem-6.test.js
index f335a1f..844b662 100644
--- a/problem-6/problem-6.test.js
+++ b/problem-6/problem-6.test.js
@@ -1,4 +1,65 @@
+const isFirstLesserThanSecond = (a, b) => a < b;
+
+const exchange = (array, index1, index2) => {
+  [array[index1], array[index2]] = [array[index2], array[index1]];
+};
+const shuffle = (array) => {
+  let randomIndex;
+
+  for (let i = array.length; i > 0; i--) {
+    randomIndex = Math.floor(Math.random() * i);
+    i--;
+
+    [array[i], array[randomIndex]] = [array[randomIndex], array[i]];
+  }
+};
+
+const partition = (array, low, high) => {
+  let left = low + 1;
+  let right = high;
+
+  const pivot = array[low];
+
+  while (true) {
+    while (isFirstLesserThanSecond(array[left], pivot)) {
+      if (left === high) {
+        break;
+      }
+
+      left++;
+    }
+
+    while (isFirstLesserThanSecond(pivot, array[right])) {
+      if (right === low) {
+        break;
+      }
+
+      right--;
+    }
+
+    if (left >= right) {
+      break;
+    }
+
+    exchange(array, left, right);
+  }
+
+  exchange(array, low, right);
+  return right;
+};
+const sort = (array, low, high) => {
+  if (low >= high) {
+    return;
+  }
+
+  const partitionIndex = partition(array, low, high);
+  sort(array, low, partitionIndex - 1);
+  sort(array, partitionIndex + 1, high);
+};
+
 const quickSort = (array) => {
+  shuffle(array);
+  sort(array, 0, array.length - 1);
 };
 
 test.each([
diff --git a/problem-6/quick-sort-code-01.png b/problem-6/quick-sort-code-01.png
new file mode 100644
index 0000000..5e60e65
Binary files /dev/null and b/problem-6/quick-sort-code-01.png differ
diff --git a/problem-6/quick-sort-code-02.png b/problem-6/quick-sort-code-02.png
new file mode 100644
index 0000000..b095e8c
Binary files /dev/null and b/problem-6/quick-sort-code-02.png differ
diff --git a/problem-6/quick-sort-code-03.png b/problem-6/quick-sort-code-03.png
new file mode 100644
index 0000000..f7e645b
Binary files /dev/null and b/problem-6/quick-sort-code-03.png differ
diff --git a/problem-6/quick-sort-code-04.png b/problem-6/quick-sort-code-04.png
new file mode 100644
index 0000000..4196895
Binary files /dev/null and b/problem-6/quick-sort-code-04.png differ
diff --git a/problem-6/quick-sort-code-05.png b/problem-6/quick-sort-code-05.png
new file mode 100644
index 0000000..bc25540
Binary files /dev/null and b/problem-6/quick-sort-code-05.png differ
diff --git a/problem-6/quick-sort-code-06.png b/problem-6/quick-sort-code-06.png
new file mode 100644
index 0000000..0edd2c0
Binary files /dev/null and b/problem-6/quick-sort-code-06.png differ
diff --git a/problem-6/quick-sort-code-07.png b/problem-6/quick-sort-code-07.png
new file mode 100644
index 0000000..111ca12
Binary files /dev/null and b/problem-6/quick-sort-code-07.png differ
diff --git a/problem-6/quick-sort-code-08.png b/problem-6/quick-sort-code-08.png
new file mode 100644
index 0000000..e961931
Binary files /dev/null and b/problem-6/quick-sort-code-08.png differ
diff --git a/problem-7/README.md b/problem-7/README.md
index 0fc24a8..afcf667 100644
--- a/problem-7/README.md
+++ b/problem-7/README.md
@@ -13,5 +13,14 @@
 ```
 
 2. 힙 정렬의 코드를 보고 어떻게 동작하는지 그림을 그려보세요. 마찬가지로 위의 값이 주어졌다고 했을 때 코드를 따라가며 그림을 그려가며 이해해 보세요.
+![heap-sort.png](heap-sort.png)
+![heap-sort-sink-01.png](heap-sort-sink-01.png)
+![heap-sort-sink-02.png](heap-sort-sink-02.png)
+![heap-sort-sink-03-01.png](heap-sort-sink-03-01.png)
+![heap-sort-sink-03-02.png](heap-sort-sink-03-02.png)
+![heap-sort-sink-04-01.png](heap-sort-sink-04-01.png)
+![heap-sort-sink-04-02.png](heap-sort-sink-04-02.png)
+![heap-sort-sink-04-03.png](heap-sort-sink-04-03.png)
+![heap-sort-sink-05.png](heap-sort-sink-05.png)
 
 3. 힙 정렬의 코드를 직접 구현해 주세요.
diff --git a/problem-7/heap-sort-sink-01.png b/problem-7/heap-sort-sink-01.png
new file mode 100644
index 0000000..8626a43
Binary files /dev/null and b/problem-7/heap-sort-sink-01.png differ
diff --git a/problem-7/heap-sort-sink-02.png b/problem-7/heap-sort-sink-02.png
new file mode 100644
index 0000000..7fe3b22
Binary files /dev/null and b/problem-7/heap-sort-sink-02.png differ
diff --git a/problem-7/heap-sort-sink-03-01.png b/problem-7/heap-sort-sink-03-01.png
new file mode 100644
index 0000000..3c98779
Binary files /dev/null and b/problem-7/heap-sort-sink-03-01.png differ
diff --git a/problem-7/heap-sort-sink-03-02.png b/problem-7/heap-sort-sink-03-02.png
new file mode 100644
index 0000000..6cc6a67
Binary files /dev/null and b/problem-7/heap-sort-sink-03-02.png differ
diff --git a/problem-7/heap-sort-sink-04-01.png b/problem-7/heap-sort-sink-04-01.png
new file mode 100644
index 0000000..4c4ba6b
Binary files /dev/null and b/problem-7/heap-sort-sink-04-01.png differ
diff --git a/problem-7/heap-sort-sink-04-02.png b/problem-7/heap-sort-sink-04-02.png
new file mode 100644
index 0000000..bd5fd1b
Binary files /dev/null and b/problem-7/heap-sort-sink-04-02.png differ
diff --git a/problem-7/heap-sort-sink-04-03.png b/problem-7/heap-sort-sink-04-03.png
new file mode 100644
index 0000000..9f089c6
Binary files /dev/null and b/problem-7/heap-sort-sink-04-03.png differ
diff --git a/problem-7/heap-sort-sink-05.png b/problem-7/heap-sort-sink-05.png
new file mode 100644
index 0000000..f787e34
Binary files /dev/null and b/problem-7/heap-sort-sink-05.png differ
diff --git a/problem-7/heap-sort.png b/problem-7/heap-sort.png
new file mode 100644
index 0000000..efaade4
Binary files /dev/null and b/problem-7/heap-sort.png differ
diff --git a/problem-7/problem-7.test.js b/problem-7/problem-7.test.js
index 8d36fec..b5d7ca5 100644
--- a/problem-7/problem-7.test.js
+++ b/problem-7/problem-7.test.js
@@ -1,4 +1,37 @@
+const exchange = (array, a, b) => {
+  [array[a], array[b]] = [array[b], array[a]];
+};
+
+const less = (a, b) => a < b;
+
+const sink = (array, i, N) => {
+  while (2 * i <= N) {
+    let j = 2 * i;
+    if (j < N && less(array[j], array[j + 1])) {
+      j++;
+    }
+
+    if (!less(array[i], array[j])) {
+      break;
+    }
+
+    exchange(array, i, j);
+    i = j;
+  }
+};
+
 const heapSort = (array) => {
+  let N = array.length - 1;
+
+  for (let i = Math.floor(N / 2); i >= 1; i--) {
+    sink(array, i, N);
+  }
+
+  while (N > 1) {
+    exchange(array, 1, N);
+    N--;
+    sink(array, 1, N);
+  }
 };
 
 test.each([