Coding challenges

gistfile1.txt

// 1 - Palindrome
const palindrome =
  "A man, a plan, a cat, a ham, a yak, a yam, a hat, a canal-Panama!";
const nonPalindrome = "levels, manaini";
const isPalindrome = (str: string) => {
  const letters = str.replace(/\W/g, "").toLocaleLowerCase();
  return (
    letters ===
    letters
      .split("")
      .reverse()
      .join("")
  );
};

// console.log(isPalindrome(palindrome));
// console.log(isPalindrome(nonPalindrome));

// 2 - Curried sum
const sum = (n1: number, n2?: number) =>
  n2 !== undefined ? n1 + n2 : (n3: number) => n1 + n3;

// console.log(sum(2, 2));
// console.log(sum(2)(2));

// 3 -
const domCrawler = (node: HTMLElement, callback: VoidFunction) => {
  if (node.hasChildNodes) {
    node.childNodes.forEach(child => {
      console.log(child);
      if (child.hasChildNodes) {
        domCollector(child, callback);
      } else {
        callback(child);
      }
    });
  } else {
    callback(child);
  }
};

// domCrawler(document.getElementById("app"), console.log);

//

function binaryGap(num) {
  // write your code in JavaScript (Node.js 8.9.4)
  const binary = num.toString(2);
  const binaryGaps = binary.match(/(0+)(?=1)/g);

  if (!binaryGaps) {
    return 0;
  }

  const largestGap = binaryGaps.reduce(
    (acc, b) => (b.length > acc ? b.length : acc),
    0
  );

  return largestGap;
}

//console.log(binaryGap(10301));

const oddOccurrencesInArray = A => {
  let odd;

  A.sort();

  const arrayLength = A.length;

  for (let index = 0; index < arrayLength; index+=2) {
    if (A[index] !== A[index + 1]) {
      odd = A[index];
      break;
    }
  }

  return odd;
};

console.log(oddOccurrencesInArray4([9, 9, 7, 3, 3]));


const cyclicRotator = (a, k) => {
  const arrayLength = a.length;
  const posRotation = k % arrayLength;

  if (!posRotation) {
    return a;
  }

  return [...a.slice(-posRotation), ...a.slice(0, -posRotation)];
};

console.log(cyclicRotator([1, 2, 3, 4, 5, 6], 7));