{
  "type": "root",
  "children": [
    {
      "type": "paragraph",
      "children": [
        {
          "type": "text",
          "value": "Use variable "
        },
        {
          "type": "subscript",
          "children": [
            {
              "type": "text",
              "value": "k"
            }
          ]
        },
        {
          "type": "text",
          "value": " in the loop."
        }
      ]
    },
    {
      "type": "paragraph",
      "children": [
        {
          "type": "subscript",
          "children": [
            {
              "type": "text",
              "value": "n"
            }
          ]
        }
      ]
    }
  ]
}