Convert flat structure to tree structure

let list = [
        {
    
          id: 1,
          label: "1",
          pid: 0,
        },
        {
    
          id: 11,
          pid: 1,
          label: "1-1",
        },
        {
    
          id: 111,
          pid: 11,
          label: "1-1-1",
        },
        {
    
          id: 2,
          label: "2",
          pid: 0,
        },
        {
    
          id: 22,
          pid: 2,
          label: "2-2",
        },
      ];

      function tranListToTreeData(list, rootValue) {
    
        var arr = [];
        list.forEach((item) => {
    
          if (item.pid === rootValue) {
    
            //  After finding it   I'm going to find  item  Is there any child node below 
            const children = tranListToTreeData(list, item.id);
            if (children.length) {
    
              //  If children Is longer than 0  Indicates that the child node is found 
              item.children = children;
            }
            arr.push(item); //  Add the contents to the array 
          }
        });
        return arr;
      }
      let result = tranListToTreeData(list, 0);
      //  Converted list The tree structure is 
      [{
    
          id: 1,
          pid: 0,
          label: "1",
          children: [{
    
              id: 11,
              pid: 1,
              label: "1-1",
              children: [{
    
                  id: 111,
                  pid: 11,
                  label: "1-1-1",
              }]
          }]
      },{
    
          id: 2,
          pid: 0,
          label: '2',
          children: [{
    
              id: 22,
              pid: 2,
              label: '2-2'
          }]
      }]