freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-javascript/68b7687dded630607aceccb1.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
68b7687dded630607aceccb1	Challenge 48: Spam Detector	28	challenge-48

--description--

Given a phone number in the format "+A (BBB) CCC-DDDD", where each letter represents a digit as follows:

• A represents the country code and can be any number of digits.
• BBB represents the area code and will always be three digits.
• CCC and DDDD represent the local number and will always be three and four digits long, respectively.

Determine if it's a spam number based on the following criteria:

• The country code is greater than 2 digits long or doesn't begin with a zero (0).
• The area code is greater than 900 or less than 200.
• The sum of first three digits of the local number appears within last four digits of the local number.
• The number has the same digit four or more times in a row (ignoring the formatting characters).

--hints--

isSpam("+0 (200) 234-0182") should return false.

assert.isFalse(isSpam("+0 (200) 234-0182"));

isSpam("+091 (555) 309-1922") should return true.

assert.isTrue(isSpam("+091 (555) 309-1922"));

isSpam("+1 (555) 435-4792") should return true.

assert.isTrue(isSpam("+1 (555) 435-4792"));

isSpam("+0 (955) 234-4364") should return true.

assert.isTrue(isSpam("+0 (955) 234-4364"));

isSpam("+0 (155) 131-6943") should return true.

assert.isTrue(isSpam("+0 (155) 131-6943"));

isSpam("+0 (555) 135-0192") should return true.

assert.isTrue(isSpam("+0 (555) 135-0192"));

isSpam("+0 (555) 564-1987") should return true.

assert.isTrue(isSpam("+0 (555) 564-1987"));

isSpam("+00 (555) 234-0182") should return false.

assert.isFalse(isSpam("+00 (555) 234-0182"));

--seed--

--seed-contents--

function isSpam(number) {

  return number;
}

--solutions--

function isSpam(number) {
  const match = number.match(/^\+(\d+)\s\((\d{3})\)\s(\d{3})-(\d{4})$/);
  const [, countryCode, areaCode, ccc, dddd] = match;
  const allDigits = countryCode + areaCode + ccc + dddd;
  
  if (countryCode.length > 2 || !countryCode.startsWith("0")) return true;

  const areaNum = parseInt(areaCode, 10);
  if (areaNum > 900 || areaNum < 200) return true;

  const sumCCC = ccc.split("").reduce((a, b) => a + parseInt(b), 0);
  if (dddd.includes(sumCCC.toString())) return true;

  if (/(\d)\1\1\1/.test(allDigits)) return true;

  return false;
}