pyramid.js

function createPyramid(base){
  if (base%2 == 0){
    throw "Pyramid base must be odd number"
  }

  var left = createLeftSide(base);
  var right = createRightSide(base);
  var final = [];
  for (var i = 0; i < left.length; i++) {
    final[i] = left[i].concat(right[i]);
  }

  return print(final);

  ///////////////////////////////////

  function createLeftSide(num){
    function createLeftRow(lNum, start, lSize){
      var lRow = [];
      for (var i = lNum; i > 0; i--) {
        lRow.push(start);
        start = start === 0 ? " " : 0;
      }
      while (lRow.length!=lSize) {
        lRow.unshift(" ");
      }
      return lRow
    }
    var lArr = [];
    var lSize = Math.floor(num / 2);
    for (var i = lSize; i >= 0; i--) {
      lArr.push(createLeftRow(i, 0, lSize));
    }
    return lArr;
  }

  function createRightSide(num){
    function createRightRow(rNum, start, rSize){
      var rRow = [];
      for (var i = rNum; i > 0; i--) {
        rRow.push((start === 0 ? " " : 0));
        start = start === 0 ? " " : 0;
      }
      while (rRow.length!=rSize) {
        rRow.push(" ");
      }
      return rRow
    }
    var rArr = [];
    var rSize = Math.ceil(num / 2);
    for (var i = rSize; i > 0; i--) {
      rArr.push(createRightRow(i, (i%2==0 ? 0 : " "), rSize));
    }
    return rArr;
  }

  function print(arr){
    for (var i = 0; i < arr.length; i++) {
      console.log('|' + arr[i].join('|') + '|');
    }
  }
}

createPyramid(11);