const pyramidOfAsterisks = function(val) {
  var arr=[];
  for (let m = 1; m <= val; m  ) {
      if (m === 7)
          break;
      for (let s = 1; s <= val - m; s  ) {
          document.write("&nbsp;&nbsp;&nbsp");
      }
      for (let n = 1; n <= m; n  ) {
          document.write("* ");
      }
      for (let p = 2; p <= m; p  ) {

          document.write("* ");
      }
      document.write("<br />");

      arr.push()
  }
} 


var pyramid = pyramidOfAsterisks(12);
        document.write(pyramid);

I have tried to display the output inside the given empty array., so i pushed the function into the array , but not displaying inside the array.

CodePudding user response：

1. You never push anything to the array arr
2. You never return anything in pyramidOfAsterisks which is why it prints undefined

Replace document.write with arr.push and return arr before the end of pyramidOfAsterisks.

const pyramidOfAsterisks = function(val) {
  var arr=[];
  for (let m = 1; m <= val; m  ) {
      if (m === 7)
          break;
      for (let s = 1; s <= val - m; s  ) {
          arr.push("&nbsp;&nbsp;&nbsp");
      }
      for (let n = 1; n <= m; n  ) {
          arr.push("* ");
      }
      for (let p = 2; p <= m; p  ) {

          arr.push("* ");
      }
      arr.push("<br />");

      //arr.push()
  };

  return arr
} 

//REM: Be aware of array.join
var pyramid = pyramidOfAsterisks(12);
document.write(pyramid.join(''));

CodePudding user response：

In the arr.push() function input the value you want to add to the array.

For example

arr.push("one")
arr.push("two")

// It will return ["one","two"]

CodePudding user response：

const pyramidOfAsterisks = function(val) {
// var arr=[];
for (let m = 1; m <= val; m  ) {
  if (m === 7)
      break;
  for (let s = 1; s <= val - m; s  ) {
      document.write("&nbsp;&nbsp;&nbsp");
  }
  for (let n = 1; n <= m; n  ) {
      document.write("* ");
  }
  for (let p = 2; p <= m; p  ) {

      document.write("* ");
  }
  document.write("<br />");

  // arr.push()
 }
} 


var pyramid = pyramidOfAsterisks(12);
    // document.write(pyramid); 

This code works fine. It outputs undefined because of the document.write in the end. pyramidOfAsterisks does not return any value yet you assign the value it returns to a variable named pyramid, this is why pyramid is equal to undefined