concept.txt

x ->
    i -> n -> _ -> q -> n -> 2
    _ -> q -> i -> n -> g -> 4 -> n ->
                                       3
                                       i -> a -> n -> _

example.txt

xin_qn2
x_qing4n3
x_qing4nian_

full.txt

xin_qn2
x_qing4n3
x_qing4nian_
x_qn2
xinqingnian_
xinqingnian1
xin1qn2
xin1qing4n3
xin1qing4nian1
x1qing4n3
x1qing4nian_
x1qn2

output.json

{
  "name": "x",
  "children": [
    {
      "name": "i",
      "children": [
        {
          "name": "n"
        },
        {
          "name": "_"
        },
        {
          "name": "q"
        },
        {
          "name": "n"
        },
        {
          "name": "2"
        }
      ]
    },
    {
      "name": "_",
      "children": [
        {
          "name": "q"
        },
        {
          "name": "i"
        },
        {
          "name": "n"
        },
        {
          "name": "g"
        },
        {
          "name": "4"
        },
        {
          "name": "n",
          "children": [
            {
              "name": "3"
            },
            {
              "name": "i",
              "children": [
                {
                  "name": "a"
                },
                {
                  "name": "n"
                },
                {
                  "name": "_"
                }
              ]
            }
          ]
        }
      ]
    }
  ]
}