javascript interview question - findIntersection

index.js

/**
 * https://dev.to/coderbyte/a-common-coding-interview-question-461f
 * https://jsfiddle.net/ronapelbaum/yLkbg4v1/
 */
function sol1(arr1, arr2) {
  // O(n*m)
  return arr1.filter(d => arr2.includes(d));
}

function sol2(arr1, arr2) {
	// O(n+m)
	const res = [];
  let pop1 = arr1.shift();
  let pop2 = arr2.shift();
  while (pop1 && pop2) {
  	if (pop1 === pop2) {
      res.push(pop1);
      pop1 = arr1.shift();
      pop2 = arr2.shift();
    } else if (pop1 > pop2) {
    	pop2 = arr2.shift();
    } else if (pop2 > pop1) {
    	pop1 = arr1.shift();
    }
  }
  return res;
}

function findIntersection(arr, solFunc) {
 const arr1 = arr[0].split(',').map(d => parseInt(d));
 const arr2 = arr[1].split(',').map(d => parseInt(d));
 const res = solFunc(arr1, arr2);
 return res.join(',');
}

// =======================================
// should be "4, 13"
const input = ["3, 4, 7, 13", "1, 2, 4, 5, 6, 13, 15"];
console.log('findIntersection sol1', findIntersection(input, sol1));
console.log('findIntersection sol2', findIntersection(input, sol2));