Longest Block in String

// Longest Block in String

const input = ['abbb'];
const print = this.print || console.log;
const gets = this.gets || ((arr, index) => () => arr[index++])(input, 0);

const strA = gets().split(''); // print(strA) // [ 'h', 'o', 'o', 'p', 'a' ]
let arrN = [];
let countMax = 1;
let count = 1;

if (strA.length >= 2) {
  for (let i = 0; i < strA.length - 1; i++) {
    if (strA[i] === strA[i + 1]) {
      count++;
      if (count > countMax) {
        countMax = count;
        arrN = [];
        for (let j = 0; j < countMax; j++) {
          arrN.push(strA[i]);
        }
      }
    } else {
      count = 1;
    }
  }
}

print(arrN.join(''));