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{Breadth-First Print}

The Question

 Breakdown

  1. Make a tree
  2. Figure out how to store the nodes
  3. Write function that walks though tree and stores the nodes
  4. Log the stored nodes to the console

1. Make a tree

var myTree = {
  value: 'A',
  children: [{
    value: 'B',
    children: [{
      value: 'D',
      children: [{
        value: 'H',
        children: []
      }]
    }]
  }, {
    value: 'C',
    children: [{
      value: 'E',
      children: []
    }, {
      value: 'F',
      children: [{
        value: 'I',
        children: []
      }, {
        value: 'J',
        children: []
      }]
    }, {
      value: 'G',
      children: []
    }]
  }]
};

2. Figure out how to store nodes 


// We want to use a hash ... basically an array of arrays 
// for example


// var myHash = [["hello", "I am here"], ["yes hello", "I am in the hash to"],["me too"],[42]];

// the first element of the hash is said to be the lowest level
// the last element is said to be the highest level
// we will store each level of the tree as a level in the hash
// and then print the hash when we are done!


// we want to make this


var hash = [[firstNode], [secondNode, thirdNode], [forthNode, fifthNode, sixNode, seventhNode]]


//from this

                    1               // level 1
                2       3           // level 2
               4     5 6 7 7        // level 3

3. Write a function that walks through the tree and stores the nodes 



function printTreeLevels (startingNode) {
  var levels = [];
  
  (function collectVals (node, level) {
    // if there is no level this deep yet, make it
    levels[ level ] = levels[ level ] || [];
    levels[ level ].push( node.value );
    // recursively handle each child node, one level deeper
    node.children.forEach(function (childNode) {
      collectVals( childNode, level+1 );
    });
  })( startingNode, 0 );

}

4. Log the stored nodes to the console 



function printTreeLevels (startingNode) {
  var levels = [];
  
  (function collectVals (node, level) {
    // if there is no level this deep yet, make it
    levels[ level ] = levels[ level ] || [];
    levels[ level ].push( node.value );
    // recursively handle each child node, one level deeper
    node.children.forEach(function (childNode) {
      collectVals( childNode, level+1 );
    });
  })( startingNode, 0 );

    
  // Print the results
  levels.forEach(function (level) {
    console.log( level.join(' ') );
  });

}

Conclusion  

There are a few ways to do this problem ... this is just one solution ... go look them up on the GOOGLs 

And also,