Number Diamond - PhillyDev Slack #daily_programmer - 20180219

dp20180219.js

const numberDiamond_1 = function() {
  const padding = new Array(9).join(' ');
  const numbers = new Array(9)
    .fill(0)
    .map((v, i) => i + 1)
    .join('');
  let halfDiamond = new Array(9).fill(0).map((v, i) => {
    let halfRow = padding.slice(0, 8 - i) + numbers.slice(0, i + 1);
    return (
      halfRow +
      halfRow
        .split('')
        .reverse()
        .join('')
        .slice(1)
    );
  });
  return halfDiamond
    .concat(
      halfDiamond
        .slice()
        .reverse()
        .slice(1)
    )
    .join('\n');
};

const numberDiamond_2 = function() {
  const padding = new Array(9).fill(' ');
  const numbers = new Array(9).fill(0).map((v, i) => i + 1);
  let halfDiamond = new Array(9).fill(0).map((v, i) => {
    let halfRow = padding.slice(0, 8 - i).concat(numbers.slice(0, i + 1));
    return halfRow.concat(
      halfRow
        .slice()
        .reverse()
        .slice(1)
    );
  });
  return halfDiamond
    .concat(
      halfDiamond
        .slice()
        .reverse()
        .slice(1)
    )
    .map(v => v.join(''))
    .join('\n');
};

const numberDiamond = numberDiamond_2;

console.log(numberDiamond());