問題一：寫出冒泡排序

void bubble_sort(int arr[], int len)
{
    for (int i = 0; i < len - 1; i++) {
        for (int j = len - 1; j > i; j--) {
           if (arr[j] < arr[j - 1]) {
            int temp = arr[j];
            arr[j] = arr[j - 1];
            arr[j - 1] = temp;
         }
      }
  }
}

問題二：寫出選擇法排序

void select_sort(int arr[], int len)
{
    for (int i = 0; i < len; i++) {
        int index = i;
        for (int j = i + 1; j < len; j++) {
            if (arr[j] < arr[index])
                index = j;
         }
         if (index != i)
         {
            int temp = arr[i];
            arr[i] = arr[index];
            arr[index] = temp; 
        }
    }
}