var findLargestLev = function(node) {
  // your code here
  var levelCnt = 0;
  var levelCounter = {};
  var nextLeftNode;
  var nextRightNode;

  var findLevelSum = function (nodeLeft, nodeRight) {
      levelCnt++;
      var levelSum = 0;
      if(nodeLeft !== undefined) {
          levelSum+=nodeLeft.data
      }
      if(nodeRight !== undefined) {
          levelSum+=nodeRight.data
      }
      levelCounter[levelCnt] = levelSum;

      if(nodeLeft.left !== undefined){
          nextLeftNode = nodeLeft.left
      } else {
          nextLeftNode = undefined
      }
      if(nodeLeft.right !== undefined){
          nextLeftNode = nodeLeft.left
      } else {
          nextLeftNode = undefined
      }
  }

  if(levelCnt === 0) {
      findLevelSum(node);
  }

  if(nextLeftNode === undefined && node.right === undefined) {
      return levelCounter
  } else if (node.left !== undefined && node.right !== undefined) {
      findLevelSum(node.left, node.right)
  } else if (node.left !== undefined && node.right === undefined) {
      findLevelSum(node.left, undefined)
  } else if (node.left === undefined && node.right !== undefined) {
      findLevelSum(undefined, node.right)
  }

  var levelTotals = Object.values(levelCounter);
  var levels = Object.keys(levelCounter);
  var largestLevelSum = levelTotals[0]
  var largestLevel = levels[0]
  for (var i = 0; i < levelTotals.length; i ++) {
      if (levelTotals[i] > largestLevelSum) {
          largestLevelSum = levelTotals[i]
          largestLevel = levels[i]
      }
  }
  return Number(largestLevel);

};